diff --git a/java/001. Two Sum.java b/java/001. Two Sum.java
index dd744ad..e69de29 100644
--- a/java/001. Two Sum.java	
+++ b/java/001. Two Sum.java	
@@ -1,18 +0,0 @@
-public class Solution {
-    public int[] twoSum(int[] numbers, int target) {
-        int[] res = new int[2];
-        Map map = new HashMap();
-        for (int i = 0; i < numbers.length; i++) {
-            map.put(numbers[i], i);
-        }
-        for (int i = 0; i < numbers.length; i++) {
-            int gap = target - numbers[i];
-            if (map.get(gap) != null && (int) map.get(gap) != i) {
-                res[0] = i + 1;
-                res[1] = (int) map.get(gap) + 1;
-                break;
-            }
-        }
-        return res;
-    }
-}
\ No newline at end of file
diff --git a/java/002. Add Two Numbers.java b/java/002. Add Two Numbers.java
index b5a515d..665b53d 100644
--- a/java/002. Add Two Numbers.java	
+++ b/java/002. Add Two Numbers.java	
@@ -8,19 +8,19 @@
  */
 public class Solution {
     public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
-    	return add(l1,l2,true);
+        return add(l1,l2,true);
     }
     public ListNode add(ListNode l1, ListNode l2,boolean flag) {
-    	boolean a=l1==null;
-    	boolean b=l2==null;
-    	if (a&&b&&flag) {
-			return null;
-		}
-    	int val=(a?0:l1.val)+(b?0:l2.val)+(flag?0:1);
-    	int v=val%10;
-    	boolean f=(v==val);
-    	ListNode answer=new ListNode(v);
-    	answer.next=add(a?null:l1.next,b?null:l2.next,f);
-    	return answer;
+        boolean a=l1==null;
+        boolean b=l2==null;
+        if (a&&b&&flag) {
+            return null;
+        }
+        int val=(a?0:l1.val)+(b?0:l2.val)+(flag?0:1);
+        int v=val%10;
+        boolean f=(v==val);
+        ListNode answer=new ListNode(v);
+        answer.next=add(a?null:l1.next,b?null:l2.next,f);
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/003. Longest Substring Without Repeating Characters.java b/java/003. Longest Substring Without Repeating Characters.java
index 0a9bf4f..35a8328 100644
--- a/java/003. Longest Substring Without Repeating Characters.java	
+++ b/java/003. Longest Substring Without Repeating Characters.java	
@@ -4,20 +4,20 @@ public int lengthOfLongestSubstring(String s) {
         Map<String,Integer> map=new HashMap<String, Integer>();
         List<String> list=new LinkedList<String>();
         for (int i = 0; i < s.length(); i++) {
-        	String k=s.substring(i, i+1);
-			if (map.get(k) != null) {
-				int n=map.get(k)-map.get(list.get(0))+1;
-				for (int j = 0; j < n; j++) {
-					map.remove(list.get(0));
-					list.remove(0);
-				}
-			}
-			map.put(k, i);
-			list.add(k);
-			if (list.size()>answer) {
-				answer=list.size();
-			}
-		}
-    	return answer;
+            String k=s.substring(i, i+1);
+            if (map.get(k) != null) {
+                int n=map.get(k)-map.get(list.get(0))+1;
+                for (int j = 0; j < n; j++) {
+                    map.remove(list.get(0));
+                    list.remove(0);
+                }
+            }
+            map.put(k, i);
+            list.add(k);
+            if (list.size()>answer) {
+                answer=list.size();
+            }
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/006. ZigZag Conversion.java b/java/006. ZigZag Conversion.java
index 4cbf70a..3b63194 100644
--- a/java/006. ZigZag Conversion.java	
+++ b/java/006. ZigZag Conversion.java	
@@ -5,28 +5,28 @@ public String convert(String s, int numRows) {
         }else{
         int k=numRows*2-2;
         String[] res=new String[numRows];
-		for (int i = 0; i < res.length; i++) {
-			res[i]="";
-		}
-			int step=0;
-		int j=0;
-		for (int i = 0; i < s.length(); i++) {
-			step++;
-			if (step<=numRows) {
-				j=step;
-			}else {
-			j=numRows-(step-numRows);
-			}
-			res[j-1]+=s.substring(i, i+1);
-			if (step==k) {
-				step=0;
-			}
-		}
-		String result="";
-		for (int i = 0; i < res.length; i++) {
-			result+=res[i];
-		}
-		return result;
+        for (int i = 0; i < res.length; i++) {
+            res[i]="";
+        }
+            int step=0;
+        int j=0;
+        for (int i = 0; i < s.length(); i++) {
+            step++;
+            if (step<=numRows) {
+                j=step;
+            }else {
+            j=numRows-(step-numRows);
+            }
+            res[j-1]+=s.substring(i, i+1);
+            if (step==k) {
+                step=0;
+            }
+        }
+        String result="";
+        for (int i = 0; i < res.length; i++) {
+            result+=res[i];
+        }
+        return result;
         }
     }
 }
\ No newline at end of file
diff --git a/java/007. Reverse Integer.java b/java/007. Reverse Integer.java
index 50de11e..3eceb9d 100644
--- a/java/007. Reverse Integer.java	
+++ b/java/007. Reverse Integer.java	
@@ -1,24 +1,24 @@
 public class Solution {
     public int reverse(int x) {
         String str=String.valueOf(x);
-		String r="";
-		int re=0;
-		if (x<0) {
-			for (int i = str.length()-1; i >0 ; i--) {
-				r+=str.substring(i,i+1);
-			}
-			r="-"+r;
-		}else {
-			for (int i = str.length()-1; i >-1 ; i--) {
-				r+=str.substring(i,i+1);
-			}
-		}
-			try {
-			re=Integer.parseInt(r);
-			
-		} catch (Exception e) {
-		
-		}
-		return re;
+        String r="";
+        int re=0;
+        if (x<0) {
+            for (int i = str.length()-1; i >0 ; i--) {
+                r+=str.substring(i,i+1);
+            }
+            r="-"+r;
+        }else {
+            for (int i = str.length()-1; i >-1 ; i--) {
+                r+=str.substring(i,i+1);
+            }
+        }
+            try {
+            re=Integer.parseInt(r);
+            
+        } catch (Exception e) {
+        
+        }
+        return re;
     }
 }
\ No newline at end of file
diff --git a/java/009. Palindrome Number.java b/java/009. Palindrome Number.java
index 5556a02..0d2fce7 100644
--- a/java/009. Palindrome Number.java	
+++ b/java/009. Palindrome Number.java	
@@ -1,35 +1,35 @@
 public class Solution {
     public boolean isPalindrome(int x) {
-		if (x < 0) {
-			return false;
-		}
-		int n = x;
-		int a = 0;
-		int p = 1;
-		while (x != 0) {
-			x /= 10;
-			a++;
-			p *= 10;
-			if (a==1) {
-				p/=10;
-			}
-		}
-		int b = a / 2;
-		if (b == 0) {
-			return true;
-		}
+        if (x < 0) {
+            return false;
+        }
+        int n = x;
+        int a = 0;
+        int p = 1;
+        while (x != 0) {
+            x /= 10;
+            a++;
+            p *= 10;
+            if (a==1) {
+                p/=10;
+            }
+        }
+        int b = a / 2;
+        if (b == 0) {
+            return true;
+        }
 
-		for (int i = 0; i < b; i++) {
-			int begin = n / p;
-			int end = n % 10;
-			if (begin != end) {
-				return false;
-			} else {
-				n = n - (begin * p);
-				p /= 100;
-				n = (n - end) / 10;
-			}
-		}
-		return true;
-	}
+        for (int i = 0; i < b; i++) {
+            int begin = n / p;
+            int end = n % 10;
+            if (begin != end) {
+                return false;
+            } else {
+                n = n - (begin * p);
+                p /= 100;
+                n = (n - end) / 10;
+            }
+        }
+        return true;
+    }
 }
\ No newline at end of file
diff --git a/java/010. Regular Expression Matching.java b/java/010. Regular Expression Matching.java
index ecca3f8..baa2f1f 100644
--- a/java/010. Regular Expression Matching.java	
+++ b/java/010. Regular Expression Matching.java	
@@ -1,53 +1,53 @@
 public class Solution {
     public boolean isMatch(String s, String p) {
         if (p.length()==0) {
-			return s.length()==0;
-		}
+            return s.length()==0;
+        }
         if (s.length()==0) {
-			if (p.length()%2!=0) {
-				return false;
-			}
-			char[] c=p.toCharArray();
-			for (int i = 1; i < c.length; i+=2) {
-				if (c[i]!=&#39;*&#39;) {
-					return false;
-				}
-			}
-			return true;
-		}
+            if (p.length()%2!=0) {
+                return false;
+            }
+            char[] c=p.toCharArray();
+            for (int i = 1; i < c.length; i+=2) {
+                if (c[i]!=&#39;*&#39;) {
+                    return false;
+                }
+            }
+            return true;
+        }
         int pl=p.length();
         int sl=s.length();
         String ep=p.substring(pl-1,pl);
         if (ep.equals("*")) {
-			if (p.substring(pl-2,pl-1).equals(".")) {
-				for (int i = sl-1; i >=0-1; i--) {
-					if (isMatch(s.substring(0, i+1),p.substring(0, pl-2))) {
-						return true;
-					}
-				}
-				return false;
-			}else {
-				String k=p.substring(pl-2,pl-1);
-				for (int i = sl-1; i >=0; i--) {
-					String t=s.substring(i,i+1);
-					if (t.equals(k)) {
-						if (isMatch(s.substring(0, i+1),p.substring(0, pl-2))) {
-							return true;
-						}
-					}else {
-						return isMatch(s.substring(0, i+1),p.substring(0, pl-2));
-					}
-				}
-				return isMatch("",p.substring(0, pl-2));
-			}
-		}else if(ep.equals(".")){
-			return isMatch(s.substring(0, sl-1),p.substring(0, pl-1));
-		}else {
-			String es=s.substring(sl-1,sl);
-			if (ep.equals(es)) {
-				return isMatch(s.substring(0, sl-1),p.substring(0, pl-1));
-			}
-			return false;
-		}
+            if (p.substring(pl-2,pl-1).equals(".")) {
+                for (int i = sl-1; i >=0-1; i--) {
+                    if (isMatch(s.substring(0, i+1),p.substring(0, pl-2))) {
+                        return true;
+                    }
+                }
+                return false;
+            }else {
+                String k=p.substring(pl-2,pl-1);
+                for (int i = sl-1; i >=0; i--) {
+                    String t=s.substring(i,i+1);
+                    if (t.equals(k)) {
+                        if (isMatch(s.substring(0, i+1),p.substring(0, pl-2))) {
+                            return true;
+                        }
+                    }else {
+                        return isMatch(s.substring(0, i+1),p.substring(0, pl-2));
+                    }
+                }
+                return isMatch("",p.substring(0, pl-2));
+            }
+        }else if(ep.equals(".")){
+            return isMatch(s.substring(0, sl-1),p.substring(0, pl-1));
+        }else {
+            String es=s.substring(sl-1,sl);
+            if (ep.equals(es)) {
+                return isMatch(s.substring(0, sl-1),p.substring(0, pl-1));
+            }
+            return false;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/011. Container With Most Water.java b/java/011. Container With Most Water.java
index b47e8dc..028d5bd 100644
--- a/java/011. Container With Most Water.java	
+++ b/java/011. Container With Most Water.java	
@@ -4,16 +4,16 @@ public int maxArea(int[] height) {
         int right=height.length-1;
         int ans=(right-left)*Math.min(height[left], height[right]);
         while (right>left) {
-        	int water=(right-left)*Math.min(height[left], height[right]);
-        	if (water>ans) {
-				ans=water;
-			}
-        	if (height[left]<height[right]) {
-				left++;
-			}else {
-				right--;
-			}
-		}
+            int water=(right-left)*Math.min(height[left], height[right]);
+            if (water>ans) {
+                ans=water;
+            }
+            if (height[left]<height[right]) {
+                left++;
+            }else {
+                right--;
+            }
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/012. Integer to Roman.java b/java/012. Integer to Roman.java
index 1848f3c..6dc8b17 100644
--- a/java/012. Integer to Roman.java	
+++ b/java/012. Integer to Roman.java	
@@ -1,131 +1,131 @@
 public class Solution {
     public String intToRoman(int num) {
       String a = "";
-		String b = "";
-		String c = "";
-		String d = "";
-		int ia = num / 1000;
-		int ib = (num / 100) % 10;
-		int ic = (num / 10) % 10;
-		int id = num % 10;
-		switch (id) {
-		case 0:
-			d = "";
-			break;
-		case 1:
-			d = "I";
-			break;
-		case 2:
-			d = "II";
-			break;
-		case 3:
-			d = "III";
-			break;
-		case 4:
-			d = "IV";
-			break;
-		case 5:
-			d = "V";
-			break;
-		case 6:
-			d = "VI";
-			break;
-		case 7:
-			d = "VII";
-			break;
-		case 8:
-			d = "VIII";
-			break;
-		case 9:
-			d = "IX";
-			break;
-		default:
-			break;
-		}
-		switch (ic) {
-		case 0:
-			c = "";
-			break;
-		case 1:
-			c = "X";
-			break;
-		case 2:
-			c = "XX";
-			break;
-		case 3:
-			c = "XXX";
-			break;
-		case 4:
-			c = "XL";
-			break;
-		case 5:
-			c = "L";
-			break;
-		case 6:
-			c = "LX";
-			break;
-		case 7:
-			c = "LXX";
-			break;
-		case 8:
-			c = "LXXX";
-			break;
-		case 9:
-			c = "XC";
-			break;
-		default:
-			break;
-		}
-			switch (ib) {
-		case 0:
-			b = "";
-			break;
-		case 1:
-			b = "C";
-			break;
-		case 2:
-			b = "CC";
-			break;
-		case 3:
-			b = "CCC";
-			break;
-		case 4:
-			b = "CD";
-			break;
-		case 5:
-			b = "D";
-			break;
-		case 6:
-			b = "DC";
-			break;
-		case 7:
-			b = "DCC";
-			break;
-		case 8:
-			b = "DCCC";
-			break;
-		case 9:
-			b = "CM";
-			break;
-		default:
-			break;
-		}
-		switch (ia) {
-		case 0:
-			a = "";
-			break;
-		case 1:
-			a = "M";
-			break;
-		case 2:
-			a = "MM";
-			break;
-		case 3:
-			a = "MMM";
-			break;
-		default:
-			break;
-		}
-		return a+b+c+d;
+        String b = "";
+        String c = "";
+        String d = "";
+        int ia = num / 1000;
+        int ib = (num / 100) % 10;
+        int ic = (num / 10) % 10;
+        int id = num % 10;
+        switch (id) {
+        case 0:
+            d = "";
+            break;
+        case 1:
+            d = "I";
+            break;
+        case 2:
+            d = "II";
+            break;
+        case 3:
+            d = "III";
+            break;
+        case 4:
+            d = "IV";
+            break;
+        case 5:
+            d = "V";
+            break;
+        case 6:
+            d = "VI";
+            break;
+        case 7:
+            d = "VII";
+            break;
+        case 8:
+            d = "VIII";
+            break;
+        case 9:
+            d = "IX";
+            break;
+        default:
+            break;
+        }
+        switch (ic) {
+        case 0:
+            c = "";
+            break;
+        case 1:
+            c = "X";
+            break;
+        case 2:
+            c = "XX";
+            break;
+        case 3:
+            c = "XXX";
+            break;
+        case 4:
+            c = "XL";
+            break;
+        case 5:
+            c = "L";
+            break;
+        case 6:
+            c = "LX";
+            break;
+        case 7:
+            c = "LXX";
+            break;
+        case 8:
+            c = "LXXX";
+            break;
+        case 9:
+            c = "XC";
+            break;
+        default:
+            break;
+        }
+            switch (ib) {
+        case 0:
+            b = "";
+            break;
+        case 1:
+            b = "C";
+            break;
+        case 2:
+            b = "CC";
+            break;
+        case 3:
+            b = "CCC";
+            break;
+        case 4:
+            b = "CD";
+            break;
+        case 5:
+            b = "D";
+            break;
+        case 6:
+            b = "DC";
+            break;
+        case 7:
+            b = "DCC";
+            break;
+        case 8:
+            b = "DCCC";
+            break;
+        case 9:
+            b = "CM";
+            break;
+        default:
+            break;
+        }
+        switch (ia) {
+        case 0:
+            a = "";
+            break;
+        case 1:
+            a = "M";
+            break;
+        case 2:
+            a = "MM";
+            break;
+        case 3:
+            a = "MMM";
+            break;
+        default:
+            break;
+        }
+        return a+b+c+d;
     }
 }
\ No newline at end of file
diff --git a/java/013. Roman to Integer.java b/java/013. Roman to Integer.java
index 0cbf162..340a2b9 100644
--- a/java/013. Roman to Integer.java	
+++ b/java/013. Roman to Integer.java	
@@ -1,82 +1,82 @@
 public class Solution {
     public int romanToInt(String s) {
-        	int a;
-	int b;
-	int c;
-	int d;
-	String sa="";
-	String sb="";
-	String sc="";
-	String sd="";
-	String flag="ǧ";
-	for (int i = 0; i < s.length(); i++) {
-		String t=s.substring(i,i+1);
-		if (flag.equals("ǧ")) {
-			if(t.equals("M")){
-				sa+=t;
-				continue;
-			}else {
-				flag="��";
-			}
-		}
-		if (flag.equals("��")) {
-			if (t.equals("C")||t.equals("D")||t.equals("M")) {
-				sb+=t;
-				continue;
-			}else {
-				flag="ʮ";
-			}
-		}
-		if (flag.equals("ʮ")) {
-			if (t.equals("X")||t.equals("L")||t.equals("C")) {
-				sc+=t;
-				continue;
-			}else {
-				flag="��";
-			}
-		}
-		if (flag.equals("��")) {
-			if (t.equals("I")||t.equals("V")||t.equals("X")) {
-				sd+=t;
-				continue;
-			}
-		}
-		
-	}
-	a=sa.length();
-	if (sb.length()==0) {
-		b=0;
-	}else if (sb.contains("M")) {
-		b=9;
-	}else if(sb.substring(0,1).equals("D")){
-		b=5+sb.length()-1;
-	}else if (sb.contains("D")) {
-		b=4;
-	}else {
-		b=sb.length();
-	}
-	if (sc.length()==0) {
-		c=0;
-	}else if (sc.contains("C")) {
-		c=9;
-	}else if(sc.substring(0,1).equals("L")){
-		c=5+sc.length()-1;
-	}else if (sc.contains("L")) {
-		c=4;
-	}else {
-		c=sc.length();
-	}
-	if (sd.length()==0) {
-		d=0;
-	}else if (sd.contains("X")) {
-		d=9;
-	}else if(sd.substring(0,1).equals("V")){
-		d=5+sd.length()-1;
-	}else if (sd.contains("V")) {
-		d=4;
-	}else {
-		d=sd.length();
-	}
-	return 1000*a+100*b+10*c+d;
+            int a;
+    int b;
+    int c;
+    int d;
+    String sa="";
+    String sb="";
+    String sc="";
+    String sd="";
+    String flag="ǧ";
+    for (int i = 0; i < s.length(); i++) {
+        String t=s.substring(i,i+1);
+        if (flag.equals("ǧ")) {
+            if(t.equals("M")){
+                sa+=t;
+                continue;
+            }else {
+                flag="��";
+            }
+        }
+        if (flag.equals("��")) {
+            if (t.equals("C")||t.equals("D")||t.equals("M")) {
+                sb+=t;
+                continue;
+            }else {
+                flag="ʮ";
+            }
+        }
+        if (flag.equals("ʮ")) {
+            if (t.equals("X")||t.equals("L")||t.equals("C")) {
+                sc+=t;
+                continue;
+            }else {
+                flag="��";
+            }
+        }
+        if (flag.equals("��")) {
+            if (t.equals("I")||t.equals("V")||t.equals("X")) {
+                sd+=t;
+                continue;
+            }
+        }
+        
+    }
+    a=sa.length();
+    if (sb.length()==0) {
+        b=0;
+    }else if (sb.contains("M")) {
+        b=9;
+    }else if(sb.substring(0,1).equals("D")){
+        b=5+sb.length()-1;
+    }else if (sb.contains("D")) {
+        b=4;
+    }else {
+        b=sb.length();
+    }
+    if (sc.length()==0) {
+        c=0;
+    }else if (sc.contains("C")) {
+        c=9;
+    }else if(sc.substring(0,1).equals("L")){
+        c=5+sc.length()-1;
+    }else if (sc.contains("L")) {
+        c=4;
+    }else {
+        c=sc.length();
+    }
+    if (sd.length()==0) {
+        d=0;
+    }else if (sd.contains("X")) {
+        d=9;
+    }else if(sd.substring(0,1).equals("V")){
+        d=5+sd.length()-1;
+    }else if (sd.contains("V")) {
+        d=4;
+    }else {
+        d=sd.length();
+    }
+    return 1000*a+100*b+10*c+d;
     }
 }
\ No newline at end of file
diff --git a/java/014. Longest Common Prefix.java b/java/014. Longest Common Prefix.java
index 85c08bc..8623746 100644
--- a/java/014. Longest Common Prefix.java	
+++ b/java/014. Longest Common Prefix.java	
@@ -1,46 +1,46 @@
 public class Solution {
     public String longestCommonPrefix(String[] strs) {
-    	if (strs.length==0) {
-			return "";
-		}
+        if (strs.length==0) {
+            return "";
+        }
         if (strs.length==1) {
-			return strs[0];
-		}
+            return strs[0];
+        }
         int n=0;
         if (strs[0].length()<strs[1].length()) {
-			n=strs[0].length();
-		}else {
-			n=strs[1].length();
-		}
+            n=strs[0].length();
+        }else {
+            n=strs[1].length();
+        }
         String answer="";
         for (int i = 0; i < n; i++) {
-        	String k0=strs[0].substring(i,i+1);
-        	String k1=strs[1].substring(i,i+1);
-        	if (k0.equals(k1)) {
-				answer+=k0;
-			}else {
-				break;
-			}
-		}
+            String k0=strs[0].substring(i,i+1);
+            String k1=strs[1].substring(i,i+1);
+            if (k0.equals(k1)) {
+                answer+=k0;
+            }else {
+                break;
+            }
+        }
         if (strs.length==2) {
-			return answer;
-		}
+            return answer;
+        }
         for (int i = 2; i < strs.length; i++) {
-        	if (answer.length()==0) {
-				return "";
-			}
-			int length=0;
-			String k="";
-			if (strs[i].length()<answer.length()) {
-				length=strs[i].length();
-			}else {
-				length=answer.length();
-			}
-			while (!answer.substring(0, length).equals(strs[i].substring(0, length))) {
-				length--;
-			}
-			answer=answer.substring(0,length);
-		}
+            if (answer.length()==0) {
+                return "";
+            }
+            int length=0;
+            String k="";
+            if (strs[i].length()<answer.length()) {
+                length=strs[i].length();
+            }else {
+                length=answer.length();
+            }
+            while (!answer.substring(0, length).equals(strs[i].substring(0, length))) {
+                length--;
+            }
+            answer=answer.substring(0,length);
+        }
         return answer;
     
         
diff --git a/java/015. 3Sum.java b/java/015. 3Sum.java
index 05baaa5..9b4de85 100644
--- a/java/015. 3Sum.java	
+++ b/java/015. 3Sum.java	
@@ -1,40 +1,40 @@
 public class Solution {
-	List<List<Integer>> ans=new ArrayList<List<Integer>>();
+    List<List<Integer>> ans=new ArrayList<List<Integer>>();
     public List<List<Integer>> threeSum(int[] nums) {
         Arrays.sort(nums);
-    	if (nums.length<3) {
-			return ans;
-		}
-    	int length=nums.length;
-    	for (int i = 0; i < length-2; i++) {
-    		if (i==0||nums[i]!=nums[i-1]) {
-    			f(nums,nums[i],i+1,length-1);
-			}
-		}
-    	return ans;
+        if (nums.length<3) {
+            return ans;
+        }
+        int length=nums.length;
+        for (int i = 0; i < length-2; i++) {
+            if (i==0||nums[i]!=nums[i-1]) {
+                f(nums,nums[i],i+1,length-1);
+            }
+        }
+        return ans;
     }
     public void f(int[] nums,int target,int s,int e){
-    	while (s<e) {
-    		int res=nums[s]+nums[e]+target;
-			if (res==0) {
-				List<Integer> list=new ArrayList<Integer>();
-				list.add(target);
-				list.add(nums[s]);
-				list.add(nums[e]);
-				ans.add(list);
-				while (s<e&&nums[s] == nums[s+1]) {
-					s++;
-				}
-				while (s<e&&nums[e] == nums[e-1]) {
-					e--;
-				}
-				s++;
-				e--;
-			}else if(res<0) {
-				s++;
-			}else {
-				e--;
-			}
-		}
+        while (s<e) {
+            int res=nums[s]+nums[e]+target;
+            if (res==0) {
+                List<Integer> list=new ArrayList<Integer>();
+                list.add(target);
+                list.add(nums[s]);
+                list.add(nums[e]);
+                ans.add(list);
+                while (s<e&&nums[s] == nums[s+1]) {
+                    s++;
+                }
+                while (s<e&&nums[e] == nums[e-1]) {
+                    e--;
+                }
+                s++;
+                e--;
+            }else if(res<0) {
+                s++;
+            }else {
+                e--;
+            }
+        }
     };
 }
\ No newline at end of file
diff --git a/java/016. 3Sum Closest.java b/java/016. 3Sum Closest.java
index d9001a6..5575feb 100644
--- a/java/016. 3Sum Closest.java	
+++ b/java/016. 3Sum Closest.java	
@@ -1,14 +1,14 @@
 public class Solution {
-	int ans=Integer.MIN_VALUE;
+    int ans=Integer.MIN_VALUE;
     public int threeSumClosest(int[] nums, int target) {
-    	Arrays.sort(nums);  
-    	int length=nums.length;  
+        Arrays.sort(nums);  
+        int length=nums.length;  
         for (int i = 0; i < length-2; i++) {  
             if (i==0||nums[i]!=nums[i-1]) {  
                 f(nums,i,i+1,length-1,target);
                 if (ans==0) {
-					return target;
-				}
+                    return target;
+                }
             }  
         }  
         return target+ans;  
@@ -25,8 +25,8 @@ public void f(int[] nums,int s,int m,int e,int target){
                 e--;  
             }
             if (ans/res!=0) {
-				ans=res;
-			}
+                ans=res;
+            }
         }  
     };  
 }
\ No newline at end of file
diff --git a/java/017. Letter Combinations of a Phone Number.java b/java/017. Letter Combinations of a Phone Number.java
index 9a95031..79691e0 100644
--- a/java/017. Letter Combinations of a Phone Number.java	
+++ b/java/017. Letter Combinations of a Phone Number.java	
@@ -1,6 +1,6 @@
 public class Solution {
     public List<String> letterCombinations(String digits) {
-	//存放答案的list
+    //存放答案的list
         List<String> list=new ArrayList<String>();
         //建立map存放手机按键
         Map<String, List<String>> map=new HashMap<String, List<String>>();
@@ -48,33 +48,33 @@ public List<String> letterCombinations(String digits) {
         map.put("9", list9);
         //循环判断
         for (int i = 0; i < digits.length(); i++) {
-			String s=digits.substring(i,i+1);
-			//如果能查到数字键盘
-			if (map.get(s)!=null) {
-				//如果list不为空，即并非刚开始
-				if (list.size()!=0) {
-					//记住目前list的长度
-					int size=list.size();
-					//循环list当前长度
-					for (int j = 0; j < size; j++) {
-						//将list中的每个值与接下来的对应数字键盘的可能性进行拼接
-						for (int k = 0; k <map.get(s).size(); k++) {
-							String a=list.get(j)+map.get(s).get(k);
-							list.add(a);
-						}
-					}
-					//删掉之前的list
-					for (int j = size-1; j >=0; j--) {
-						list.remove(j);
-					}
-				}else {
-					for (int j = 0; j < map.get(s).size(); j++) {
-						String a=map.get(s).get(j);
-						list.add(a);
-					}
-				}
-			}
-		}
+            String s=digits.substring(i,i+1);
+            //如果能查到数字键盘
+            if (map.get(s)!=null) {
+                //如果list不为空，即并非刚开始
+                if (list.size()!=0) {
+                    //记住目前list的长度
+                    int size=list.size();
+                    //循环list当前长度
+                    for (int j = 0; j < size; j++) {
+                        //将list中的每个值与接下来的对应数字键盘的可能性进行拼接
+                        for (int k = 0; k <map.get(s).size(); k++) {
+                            String a=list.get(j)+map.get(s).get(k);
+                            list.add(a);
+                        }
+                    }
+                    //删掉之前的list
+                    for (int j = size-1; j >=0; j--) {
+                        list.remove(j);
+                    }
+                }else {
+                    for (int j = 0; j < map.get(s).size(); j++) {
+                        String a=map.get(s).get(j);
+                        list.add(a);
+                    }
+                }
+            }
+        }
         return list;
     }
 }
\ No newline at end of file
diff --git a/java/018. 4Sum.java b/java/018. 4Sum.java
index 8cc6112..d31f641 100644
--- a/java/018. 4Sum.java	
+++ b/java/018. 4Sum.java	
@@ -1,45 +1,45 @@
 public class Solution {
-	List<List<Integer>> ans=new ArrayList<List<Integer>>();
+    List<List<Integer>> ans=new ArrayList<List<Integer>>();
     public List<List<Integer>> fourSum(int[] nums, int target) {
         if (nums.length<4) {
-			return ans;
-		}
-    	Arrays.sort(nums);
-    	int length=nums.length;
-    	for (int i = 0; i <length-3; i++) {
-			for (int j = length-1; j >=i+3; j--) {
-				if ((i==0||nums[i]!=nums[i-1])&&(j==length-1||nums[j]!=nums[j+1])) {
-					f(nums,target,i,i+1,j-1,j);
-				}
-			}
-		}
-    	return ans;
+            return ans;
+        }
+        Arrays.sort(nums);
+        int length=nums.length;
+        for (int i = 0; i <length-3; i++) {
+            for (int j = length-1; j >=i+3; j--) {
+                if ((i==0||nums[i]!=nums[i-1])&&(j==length-1||nums[j]!=nums[j+1])) {
+                    f(nums,target,i,i+1,j-1,j);
+                }
+            }
+        }
+        return ans;
     }
     public void f(int[] nums, int target,int s,int m,int n,int e){
-    	int is=nums[s];
-    	int ie=nums[e];
-    	while (m<n) {
-			int res=is+nums[m]+nums[n]+ie-target;
-			if (res==0) {
-				List<Integer> list=new ArrayList<Integer>();
-				list.add(is);
-				list.add(nums[m]);
-				list.add(nums[n]);
-				list.add(ie);
-				ans.add(list);
-				while (m<n&&nums[m]==nums[m+1]) {
-					m++;
-				}
-				while (m<n&&nums[n]==nums[n-1]) {
-					n--;
-				}
-				m++;
-				n--;
-			}else if(res<0){
-				m++;
-			}else{
-				n--;
-			}
-		}
+        int is=nums[s];
+        int ie=nums[e];
+        while (m<n) {
+            int res=is+nums[m]+nums[n]+ie-target;
+            if (res==0) {
+                List<Integer> list=new ArrayList<Integer>();
+                list.add(is);
+                list.add(nums[m]);
+                list.add(nums[n]);
+                list.add(ie);
+                ans.add(list);
+                while (m<n&&nums[m]==nums[m+1]) {
+                    m++;
+                }
+                while (m<n&&nums[n]==nums[n-1]) {
+                    n--;
+                }
+                m++;
+                n--;
+            }else if(res<0){
+                m++;
+            }else{
+                n--;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/019. Remove Nth Node From End of List.java b/java/019. Remove Nth Node From End of List.java
index 6369b82..816abca 100644
--- a/java/019. Remove Nth Node From End of List.java	
+++ b/java/019. Remove Nth Node From End of List.java	
@@ -11,17 +11,17 @@ public ListNode removeNthFromEnd(ListNode head, int n) {
         List<ListNode> list=new ArrayList<ListNode>();
         list=addlist(head, list);
         if (list.size()==n) {
-			return head.next;
-		}
+            return head.next;
+        }
         list.get(list.size()-n-1).next=n==1?null:list.get(list.size()-n+1);
         return head;
     }
     public  List<ListNode> addlist(ListNode head, List<ListNode> list){
-    	if (head!=null) {
-		    list.add(head);
-		}else {
-			return list;
-		}
-    	return addlist(head.next, list);
+        if (head!=null) {
+            list.add(head);
+        }else {
+            return list;
+        }
+        return addlist(head.next, list);
     }
 }
\ No newline at end of file
diff --git a/java/020. Valid Parentheses.java b/java/020. Valid Parentheses.java
index 94314d8..6c3f682 100644
--- a/java/020. Valid Parentheses.java	
+++ b/java/020. Valid Parentheses.java	
@@ -1,49 +1,49 @@
 public class Solution {
     public boolean isValid(String s) {
-	String ns="";
-	for (int i = 0; i <s.length(); i++) {
-		String k=s.substring(i,i+1);
-		if (k.equals("{")) {
-			ns+=k;
-			continue;
-		}
-		if (k.equals("[")) {
-			ns+=k;
-			continue;
-		}
-		if (k.equals("(")) {
-			ns+=k;
-			continue;
-		}
-		if (k.equals("}")) {
-			if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("{")) {
-				ns=ns.substring(0, ns.length()-1);
-				continue;
-			}else {
-				return false;	
-			}
-		}
-		if (k.equals("]")) {
-			if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("[")) {
-				ns=ns.substring(0, ns.length()-1);
-				continue;
-			}else {
-				return false;	
-			}
-		}
-		if (k.equals(")")) {
-			if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("(")) {
-				ns=ns.substring(0, ns.length()-1);
-				continue;
-			}else {
-				return false;	
-			}
-		}
-	}
-	if (ns.length()!=0) {
-		return false;
-	}else {
-		return true;
-	}
+    String ns="";
+    for (int i = 0; i <s.length(); i++) {
+        String k=s.substring(i,i+1);
+        if (k.equals("{")) {
+            ns+=k;
+            continue;
+        }
+        if (k.equals("[")) {
+            ns+=k;
+            continue;
+        }
+        if (k.equals("(")) {
+            ns+=k;
+            continue;
+        }
+        if (k.equals("}")) {
+            if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("{")) {
+                ns=ns.substring(0, ns.length()-1);
+                continue;
+            }else {
+                return false;    
+            }
+        }
+        if (k.equals("]")) {
+            if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("[")) {
+                ns=ns.substring(0, ns.length()-1);
+                continue;
+            }else {
+                return false;    
+            }
+        }
+        if (k.equals(")")) {
+            if (ns.length()>0&&ns.substring(ns.length()-1, ns.length()).equals("(")) {
+                ns=ns.substring(0, ns.length()-1);
+                continue;
+            }else {
+                return false;    
+            }
+        }
+    }
+    if (ns.length()!=0) {
+        return false;
+    }else {
+        return true;
+    }
 }
 }
\ No newline at end of file
diff --git a/java/021. Merge Two Sorted Lists.java b/java/021. Merge Two Sorted Lists.java
index 05c5282..43ace6b 100644
--- a/java/021. Merge Two Sorted Lists.java	
+++ b/java/021. Merge Two Sorted Lists.java	
@@ -8,20 +8,20 @@
  */
 public class Solution {
     public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
-    	if (l1==null) {
-			return l2;
-		}
+        if (l1==null) {
+            return l2;
+        }
         if (l2==null) {
-			return l1;
-		}
+            return l1;
+        }
         ListNode l=null;
         if (l1.val>l2.val) {
-			l=new ListNode(l2.val);
-			l.next=mergeTwoLists(l1,l2.next);
-		}else {
-			l=new ListNode(l1.val);
-			l.next=mergeTwoLists(l1.next,l2);
-		}
+            l=new ListNode(l2.val);
+            l.next=mergeTwoLists(l1,l2.next);
+        }else {
+            l=new ListNode(l1.val);
+            l.next=mergeTwoLists(l1.next,l2);
+        }
         return l;
     }
 }
\ No newline at end of file
diff --git a/java/022. Generate Parentheses.java b/java/022. Generate Parentheses.java
index 27f0dea..3fcab07 100644
--- a/java/022. Generate Parentheses.java	
+++ b/java/022. Generate Parentheses.java	
@@ -1,42 +1,42 @@
 public class Solution {
     public List<String> generateParenthesis(int n) {
-		List<String> list = new ArrayList<String>();
-		String a = "(";
-		list.add(a);
-		for (int i = 1; i <= 2 * n - 1; i++) {
-			int size = list.size();
-			for (int j = 0; j < size; j++) {
-				String s = list.get(j);
-				int use = 0;
-				int have = 0;
-				// 判断当前的字符串已经使用掉的"("和还未被")"消耗掉的"("
-				for (int k = 0; k < s.length(); k++) {
-					if (s.substring(k, k + 1).equals("(")) {
-						use++;
-						have++;
-					}
-					if (s.substring(k, k + 1).equals(")")) {
-						have--;
-					}
-				}
-				if (use == n) {
-					s += ")";
-					list.add(s);
-				} else if (have == 0) {
-					s += "(";
-					list.add(s);
-				} else {
-					String sa = s + "(";
-					String sb = s + ")";
-					list.add(sa);
-					list.add(sb);
-				}
-			}
-			for (int j = size - 1; j >= 0; j--) {
-				list.remove(j);
-			}
-		}
+        List<String> list = new ArrayList<String>();
+        String a = "(";
+        list.add(a);
+        for (int i = 1; i <= 2 * n - 1; i++) {
+            int size = list.size();
+            for (int j = 0; j < size; j++) {
+                String s = list.get(j);
+                int use = 0;
+                int have = 0;
+                // 判断当前的字符串已经使用掉的"("和还未被")"消耗掉的"("
+                for (int k = 0; k < s.length(); k++) {
+                    if (s.substring(k, k + 1).equals("(")) {
+                        use++;
+                        have++;
+                    }
+                    if (s.substring(k, k + 1).equals(")")) {
+                        have--;
+                    }
+                }
+                if (use == n) {
+                    s += ")";
+                    list.add(s);
+                } else if (have == 0) {
+                    s += "(";
+                    list.add(s);
+                } else {
+                    String sa = s + "(";
+                    String sb = s + ")";
+                    list.add(sa);
+                    list.add(sb);
+                }
+            }
+            for (int j = size - 1; j >= 0; j--) {
+                list.remove(j);
+            }
+        }
 
-		return list;
-	}
+        return list;
+    }
 }
\ No newline at end of file
diff --git a/java/023. Merge k Sorted Lists.java b/java/023. Merge k Sorted Lists.java
index 059752d..38ee0b7 100644
--- a/java/023. Merge k Sorted Lists.java	
+++ b/java/023. Merge k Sorted Lists.java	
@@ -8,24 +8,24 @@
  */
 public class Solution {
     public ListNode mergeKLists(ListNode[] lists) {
-    	if (lists.length>2) {
-    		ListNode[] l1=new ListNode[lists.length/2];
-    		ListNode[] l2=new ListNode[lists.length-lists.length/2];
-    		for (int i = 0; i < lists.length; i++) {
-				if (i<lists.length/2) {
-					l1[i]=lists[i];
-				}else {
-					l2[i-lists.length/2]=lists[i];
-				}
-			}
-			return mergeTwoLists(mergeKLists(l1),mergeKLists(l2));
-		}else if (lists.length==2){
-			return mergeTwoLists(lists[0],lists[1]);
-		}else if (lists.length==1){
-			return lists[0];
-		}else {
-			return null;
-		}
+        if (lists.length>2) {
+            ListNode[] l1=new ListNode[lists.length/2];
+            ListNode[] l2=new ListNode[lists.length-lists.length/2];
+            for (int i = 0; i < lists.length; i++) {
+                if (i<lists.length/2) {
+                    l1[i]=lists[i];
+                }else {
+                    l2[i-lists.length/2]=lists[i];
+                }
+            }
+            return mergeTwoLists(mergeKLists(l1),mergeKLists(l2));
+        }else if (lists.length==2){
+            return mergeTwoLists(lists[0],lists[1]);
+        }else if (lists.length==1){
+            return lists[0];
+        }else {
+            return null;
+        }
     }
     public ListNode mergeTwoLists(ListNode l1, ListNode l2) {  
         if (l1==null) {  
diff --git a/java/024. Swap Nodes in Pairs.java b/java/024. Swap Nodes in Pairs.java
index 59f9e48..8e8bfb7 100644
--- a/java/024. Swap Nodes in Pairs.java	
+++ b/java/024. Swap Nodes in Pairs.java	
@@ -9,13 +9,13 @@
 public class Solution {
     public ListNode swapPairs(ListNode head) {
         if (head==null||head.next==null) {
-			return head;
-		}else {
-			int val=head.val;
-			head.val=head.next.val;
-			head.next.val=val;
-			head.next.next=swapPairs(head.next.next);
-		}
+            return head;
+        }else {
+            int val=head.val;
+            head.val=head.next.val;
+            head.next.val=val;
+            head.next.next=swapPairs(head.next.next);
+        }
         return head;
     }
 }
\ No newline at end of file
diff --git a/java/025. Reverse Nodes in k-Group.java b/java/025. Reverse Nodes in k-Group.java
index 8e19f40..02f7e67 100644
--- a/java/025. Reverse Nodes in k-Group.java	
+++ b/java/025. Reverse Nodes in k-Group.java	
@@ -8,23 +8,23 @@
  */
 public class Solution {
     public ListNode reverseKGroup(ListNode head, int k) {
-		ListNode l = head;
-		List<Integer> val = new ArrayList<Integer>();
-		for (int i = 0; i < k; i++) {
-			if (l == null) {
-				return head;
-			}
-			val.add(l.val);
-			l = l.next;
-		}
-		l = head;
-		for (int i = val.size() - 1; i >= 0; i--) {
-			l.val = val.get(i);
-			l = l.next;
-		}
-		l = reverseKGroup(l, k);
-		return head;
-	}
+        ListNode l = head;
+        List<Integer> val = new ArrayList<Integer>();
+        for (int i = 0; i < k; i++) {
+            if (l == null) {
+                return head;
+            }
+            val.add(l.val);
+            l = l.next;
+        }
+        l = head;
+        for (int i = val.size() - 1; i >= 0; i--) {
+            l.val = val.get(i);
+            l = l.next;
+        }
+        l = reverseKGroup(l, k);
+        return head;
+    }
 }/**
  * Definition for singly-linked list.
  * public class ListNode {
@@ -35,21 +35,21 @@ public ListNode reverseKGroup(ListNode head, int k) {
  */
 public class Solution {
     public ListNode reverseKGroup(ListNode head, int k) {
-		ListNode l = head;
-		List<Integer> val = new ArrayList<Integer>();
-		for (int i = 0; i < k; i++) {
-			if (l == null) {
-				return head;
-			}
-			val.add(l.val);
-			l = l.next;
-		}
-		l = head;
-		for (int i = val.size() - 1; i >= 0; i--) {
-			l.val = val.get(i);
-			l = l.next;
-		}
-		l = reverseKGroup(l, k);
-		return head;
-	}
+        ListNode l = head;
+        List<Integer> val = new ArrayList<Integer>();
+        for (int i = 0; i < k; i++) {
+            if (l == null) {
+                return head;
+            }
+            val.add(l.val);
+            l = l.next;
+        }
+        l = head;
+        for (int i = val.size() - 1; i >= 0; i--) {
+            l.val = val.get(i);
+            l = l.next;
+        }
+        l = reverseKGroup(l, k);
+        return head;
+    }
 }
\ No newline at end of file
diff --git a/java/026. Remove Duplicates from Sorted Array.java b/java/026. Remove Duplicates from Sorted Array.java
index d778d4d..24b2f6d 100644
--- a/java/026. Remove Duplicates from Sorted Array.java	
+++ b/java/026. Remove Duplicates from Sorted Array.java	
@@ -3,24 +3,24 @@ public int removeDuplicates(int[] nums) {
         if(nums.length<=1){
             return nums.length;
         }
-   	int tar=nums[0];
-	int l=1;
-	int end=nums.length;
-	int kuang=0;
-	for (int i = 1; i < end; i++) {
-		if (nums[i]==tar) {
-			for (int j = i; j < end-1; j++) {
-				kuang=nums[j];
-				nums[j]=nums[j+1];
-				nums[j+1]=kuang;
-			}
-			end--;
-			i--;
-		}else {
-			tar=nums[i];
-			l++;
-		}
-	}
-	return l;
+       int tar=nums[0];
+    int l=1;
+    int end=nums.length;
+    int kuang=0;
+    for (int i = 1; i < end; i++) {
+        if (nums[i]==tar) {
+            for (int j = i; j < end-1; j++) {
+                kuang=nums[j];
+                nums[j]=nums[j+1];
+                nums[j+1]=kuang;
+            }
+            end--;
+            i--;
+        }else {
+            tar=nums[i];
+            l++;
+        }
+    }
+    return l;
     }
 }
\ No newline at end of file
diff --git a/java/027. Remove Element.java b/java/027. Remove Element.java
index 95c03bb..4110a0d 100644
--- a/java/027. Remove Element.java	
+++ b/java/027. Remove Element.java	
@@ -1,18 +1,18 @@
 public class Solution {
     public int removeElement(int[] nums, int val) {
        int end=nums.length;
-	int k=0;
-	for (int i = 0; i < end; i++) {
-		if (nums[i]==val) {
-			for (int j = i; j < end-1; j++) {
-				k=nums[j];
-				nums[j]=nums[j+1];
-				nums[j+1]=k;
-			}
-			end--;
-			i--;
-		}
-	}
-	return end;
+    int k=0;
+    for (int i = 0; i < end; i++) {
+        if (nums[i]==val) {
+            for (int j = i; j < end-1; j++) {
+                k=nums[j];
+                nums[j]=nums[j+1];
+                nums[j+1]=k;
+            }
+            end--;
+            i--;
+        }
+    }
+    return end;
     }
 }
\ No newline at end of file
diff --git a/java/028. Implement strStr().java b/java/028. Implement strStr().java
index 83a7b03..251c15f 100644
--- a/java/028. Implement strStr().java	
+++ b/java/028. Implement strStr().java	
@@ -1,13 +1,13 @@
 public class Solution {
     public int strStr(String haystack, String needle) {
         if (needle.length()==0) {
-			return 0;
-		}
+            return 0;
+        }
         for (int i = 0; i <haystack.length()-needle.length()+1; i++) {
-			if (haystack.substring(i,i+needle.length()).equals(needle)) {
-				return i;
-			}
-		}
+            if (haystack.substring(i,i+needle.length()).equals(needle)) {
+                return i;
+            }
+        }
         return -1;
     }
 }
\ No newline at end of file
diff --git a/java/031. Next Permutation.java b/java/031. Next Permutation.java
index fb12486..400bed7 100644
--- a/java/031. Next Permutation.java	
+++ b/java/031. Next Permutation.java	
@@ -1,28 +1,28 @@
 public class Solution {
     public void nextPermutation(int[] nums) {
-    	if (nums.length>1) {
+        if (nums.length>1) {
 
-        	int a=0;
-        	for (int i = 1; i < nums.length; i++) {
-    			if (nums[i]>nums[i-1]) {
-    				a=i;
-    			}
-    		}
+            int a=0;
+            for (int i = 1; i < nums.length; i++) {
+                if (nums[i]>nums[i-1]) {
+                    a=i;
+                }
+            }
             for (int i = a; i < (a+nums.length)/2; i++) {
-    			int k=nums[i];
-    			nums[i]=nums[nums.length-i+a-1];
-    			nums[nums.length-i+a-1]=k;
-    		}
+                int k=nums[i];
+                nums[i]=nums[nums.length-i+a-1];
+                nums[nums.length-i+a-1]=k;
+            }
             if (a>0) {
-            	for (int i = a; i < nums.length; i++) {
-            		if (nums[a-1]<nums[i]) {
-            			int k=nums[i];
-            			nums[i]=nums[a-1];
-            			nums[a-1]=k;
-            			break;
-            		}
-            	}
-    		}
-		}
+                for (int i = a; i < nums.length; i++) {
+                    if (nums[a-1]<nums[i]) {
+                        int k=nums[i];
+                        nums[i]=nums[a-1];
+                        nums[a-1]=k;
+                        break;
+                    }
+                }
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/032. Longest Valid Parentheses.java b/java/032. Longest Valid Parentheses.java
index 5f6714f..6636c21 100644
--- a/java/032. Longest Valid Parentheses.java	
+++ b/java/032. Longest Valid Parentheses.java	
@@ -2,21 +2,21 @@ public class Solution {
     public int longestValidParentheses(String s) {
         int length=s.length();
         if (length==0) {
-			return 0;
-		}
+            return 0;
+        }
         int ans=0;
         char[] c=s.toCharArray();
         int[] vals=new int[length];
         for (int i = length-2; i >= 0; i--) {
-        	if (c[i]==&#39;(&#39;) {
-				int t=i+1+vals[i+1];
-				if (t<length&&c[t]==&#39;)&#39;) {
-					vals[i]=vals[i+1]+2;
-					vals[i]+=((t+1<length)?vals[t+1]:0);
-					ans=ans<vals[i]?vals[i]:ans;
-				}
-			}
-		}
+            if (c[i]==&#39;(&#39;) {
+                int t=i+1+vals[i+1];
+                if (t<length&&c[t]==&#39;)&#39;) {
+                    vals[i]=vals[i+1]+2;
+                    vals[i]+=((t+1<length)?vals[t+1]:0);
+                    ans=ans<vals[i]?vals[i]:ans;
+                }
+            }
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/033. Search in Rotated Sorted Array.java b/java/033. Search in Rotated Sorted Array.java
index e3fbc00..97a8c60 100644
--- a/java/033. Search in Rotated Sorted Array.java	
+++ b/java/033. Search in Rotated Sorted Array.java	
@@ -1,63 +1,63 @@
 public class Solution {
     public int search(int[] nums, int target) {
-		if (nums.length==1) {
-			if (nums[0]==target) {
-				return 0;
-			}else {
-				return -1;
-			}
-		}
-		int begin=0;
-		int end=nums.length-1;
-		int half=(end+begin)/2;
-		while (end-begin>1) {
-			int b=nums[begin];
-			int h=nums[half];
-			int e=nums[end];
-			if (h==target) {
-				return half;
-			}
-			if (b==target) {
-				return begin;
-			}
-			if (e==target) {
-				return end;
-			}
-			if (h>b) {
-				if (target>h) {
-					begin=half;
-					half=(end+begin)/2;
-				}else {
-					if (target>b) {
-						end=half;
-						half=(end+begin)/2;
-					}else {
-						begin=half;
-						half=(end+begin)/2;
-					}
-				}
-			}else {
-				if (target<h) {
-					end=half;
-					half=(end+begin)/2;
-				}else {
-					if (target>e) {
-						end=half;
-						half=(end+begin)/2;
-					}else {
-						begin=half;
-						half=(end+begin)/2;
-					}
-				}
-			}
-		}
-		if (nums[begin]==target) {
-			return begin;
-		}
-		if (nums[end]==target) {
-			return end;
-		}
+        if (nums.length==1) {
+            if (nums[0]==target) {
+                return 0;
+            }else {
+                return -1;
+            }
+        }
+        int begin=0;
+        int end=nums.length-1;
+        int half=(end+begin)/2;
+        while (end-begin>1) {
+            int b=nums[begin];
+            int h=nums[half];
+            int e=nums[end];
+            if (h==target) {
+                return half;
+            }
+            if (b==target) {
+                return begin;
+            }
+            if (e==target) {
+                return end;
+            }
+            if (h>b) {
+                if (target>h) {
+                    begin=half;
+                    half=(end+begin)/2;
+                }else {
+                    if (target>b) {
+                        end=half;
+                        half=(end+begin)/2;
+                    }else {
+                        begin=half;
+                        half=(end+begin)/2;
+                    }
+                }
+            }else {
+                if (target<h) {
+                    end=half;
+                    half=(end+begin)/2;
+                }else {
+                    if (target>e) {
+                        end=half;
+                        half=(end+begin)/2;
+                    }else {
+                        begin=half;
+                        half=(end+begin)/2;
+                    }
+                }
+            }
+        }
+        if (nums[begin]==target) {
+            return begin;
+        }
+        if (nums[end]==target) {
+            return end;
+        }
 
-		return -1;
-	}
+        return -1;
+    }
 }
\ No newline at end of file
diff --git a/java/034. Search for a Range.java b/java/034. Search for a Range.java
index 67f62c7..607edfc 100644
--- a/java/034. Search for a Range.java	
+++ b/java/034. Search for a Range.java	
@@ -1,72 +1,72 @@
 public class Solution {
     public int[] searchRange(int[] nums, int target) {
         int begin=0;
-		int end=nums.length-1;
-		int a=(begin+end)/2;
-		int[] answer=new int[2];
-		while (nums[a]!=target) {
-		    if(begin==end){
-		        answer[0]=-1;
-		        answer[1]=-1;
-		        return answer;
-		    }
-		if (nums[a]>target) {
-				if (a==end) {
-					end--;
-				}else {
-					end=a;
-				}
-				
-			}else {
-				if (a==begin) {
-					begin++;
-				}else {
-					begin=a;
-				}
-				
-			}
-			a=(begin+end)/2;
-		}
-		int bb=0;
-		int be=a;
-		int ba=(bb+be)/2;
-			while (!(nums[ba]==target&&(ba==0||nums[ba-1]!=target))) {
-			if (nums[ba]>=target) {
-				if (ba==be) {
-					be--;
-				}else {
-					be=ba;
-				}
-			}else {
-				if (ba==bb) {
-					bb++;
-				}else {
-					bb=ba;
-				}
-			}
-			ba=(bb+be)/2;
-		}
-		int eb=a;
-		int ee=nums.length-1;
-		int ea=(eb+ee)/2;
+        int end=nums.length-1;
+        int a=(begin+end)/2;
+        int[] answer=new int[2];
+        while (nums[a]!=target) {
+            if(begin==end){
+                answer[0]=-1;
+                answer[1]=-1;
+                return answer;
+            }
+        if (nums[a]>target) {
+                if (a==end) {
+                    end--;
+                }else {
+                    end=a;
+                }
+                
+            }else {
+                if (a==begin) {
+                    begin++;
+                }else {
+                    begin=a;
+                }
+                
+            }
+            a=(begin+end)/2;
+        }
+        int bb=0;
+        int be=a;
+        int ba=(bb+be)/2;
+            while (!(nums[ba]==target&&(ba==0||nums[ba-1]!=target))) {
+            if (nums[ba]>=target) {
+                if (ba==be) {
+                    be--;
+                }else {
+                    be=ba;
+                }
+            }else {
+                if (ba==bb) {
+                    bb++;
+                }else {
+                    bb=ba;
+                }
+            }
+            ba=(bb+be)/2;
+        }
+        int eb=a;
+        int ee=nums.length-1;
+        int ea=(eb+ee)/2;
 while (!(nums[ea]==target&&(ea==nums.length-1||nums[ea+1]!=target))) {
-			if (nums[ea]<=target) {
-				if (ea==eb) {
-					eb++;
-				}else {
-					eb=ea;
-				}
-			}else {
-				if (ea==ee) {
-					ee--;
-				}else {
-					ee=ea;
-				}
-				}
-			ea=(eb+ee)/2;
-		}
-		     answer[0]=ba;
-		        answer[1]=ea;
-		return answer;
+            if (nums[ea]<=target) {
+                if (ea==eb) {
+                    eb++;
+                }else {
+                    eb=ea;
+                }
+            }else {
+                if (ea==ee) {
+                    ee--;
+                }else {
+                    ee=ea;
+                }
+                }
+            ea=(eb+ee)/2;
+        }
+             answer[0]=ba;
+                answer[1]=ea;
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/035. Search Insert Position.java b/java/035. Search Insert Position.java
index 109aab1..0903be1 100644
--- a/java/035. Search Insert Position.java	
+++ b/java/035. Search Insert Position.java	
@@ -1,33 +1,33 @@
 public class Solution {
     public int searchInsert(int[] nums, int target) {
         int begin=0;
-		int end=nums.length-1;
-		int a=(begin+end)/2;
-		if (target<nums[0]) {
-			return 0;
-		}
-		if (target>nums[nums.length-1]) {
-		return nums.length;
-		}
-		while (nums[a]!=target) {
-			if (end-1==begin&&(nums[begin]<target&&target<nums[end])) {
-				return end;
-			}
-			if (nums[a]>target) {
-				if (end==a) {
-					end--;
-				}else {
-					end=a;
-				}
-			}else {
-				if (begin==a) {
-					begin++;
-				}else {
-					begin=a;
-				}
-			}
-			a=(begin+end)/2;
-		}
-			return a;
+        int end=nums.length-1;
+        int a=(begin+end)/2;
+        if (target<nums[0]) {
+            return 0;
+        }
+        if (target>nums[nums.length-1]) {
+        return nums.length;
+        }
+        while (nums[a]!=target) {
+            if (end-1==begin&&(nums[begin]<target&&target<nums[end])) {
+                return end;
+            }
+            if (nums[a]>target) {
+                if (end==a) {
+                    end--;
+                }else {
+                    end=a;
+                }
+            }else {
+                if (begin==a) {
+                    begin++;
+                }else {
+                    begin=a;
+                }
+            }
+            a=(begin+end)/2;
+        }
+            return a;
     }
 }
\ No newline at end of file
diff --git a/java/036. Valid Sudoku.java b/java/036. Valid Sudoku.java
index 3ab4779..c9ffe01 100644
--- a/java/036. Valid Sudoku.java	
+++ b/java/036. Valid Sudoku.java	
@@ -1,43 +1,43 @@
 public class Solution {
     public boolean isValidSudoku(char[][] board) {
-		//验证每行每列有没有重复数据
-		for (int i = 0; i < 9; i++) {
-			Map<Character, String> cross=new HashMap<Character, String>();
-			Map<Character, String> vertical=new HashMap<Character, String>();
-			for (int j = 0; j < 9; j++) {
-				if (!(board[i][j]==&#39;.&#39;)) {
-					if (cross.get(board[i][j])!=null) {
-						return false;
-					}else {
-						cross.put(board[i][j], "");
-					}
-				}
-				if (board[j][i]!=&#39;.&#39;) {
-					if (vertical.get(board[j][i])!=null) {
-						return false;
-					}else {
-						vertical.put(board[j][i], "");
-					}
-				}
-			}
-		}
-		//验证每个小九个字有无重复数据
-		for (int a = 0; a < 3; a++) {
-			for (int b = 0; b < 3; b++) {
-				Map<Character, String> squ=new HashMap<Character, String>();
-				for (int c = 0; c < 3; c++) {
-					for (int d = 0; d < 3; d++) {
-					if (board[3*a+c][3*b+d]!=&#39;.&#39;) {
-						if (squ.get(board[3*a+c][3*b+d])!=null) {
-							return false;
-						}else {
-							squ.put(board[3*a+c][3*b+d], "");
-						}
-					}
-					}
-				}
-			}
-		}
-	return true;
+        //验证每行每列有没有重复数据
+        for (int i = 0; i < 9; i++) {
+            Map<Character, String> cross=new HashMap<Character, String>();
+            Map<Character, String> vertical=new HashMap<Character, String>();
+            for (int j = 0; j < 9; j++) {
+                if (!(board[i][j]==&#39;.&#39;)) {
+                    if (cross.get(board[i][j])!=null) {
+                        return false;
+                    }else {
+                        cross.put(board[i][j], "");
+                    }
+                }
+                if (board[j][i]!=&#39;.&#39;) {
+                    if (vertical.get(board[j][i])!=null) {
+                        return false;
+                    }else {
+                        vertical.put(board[j][i], "");
+                    }
+                }
+            }
+        }
+        //验证每个小九个字有无重复数据
+        for (int a = 0; a < 3; a++) {
+            for (int b = 0; b < 3; b++) {
+                Map<Character, String> squ=new HashMap<Character, String>();
+                for (int c = 0; c < 3; c++) {
+                    for (int d = 0; d < 3; d++) {
+                    if (board[3*a+c][3*b+d]!=&#39;.&#39;) {
+                        if (squ.get(board[3*a+c][3*b+d])!=null) {
+                            return false;
+                        }else {
+                            squ.put(board[3*a+c][3*b+d], "");
+                        }
+                    }
+                    }
+                }
+            }
+        }
+    return true;
     }
 }
\ No newline at end of file
diff --git a/java/037. Sudoku Solver.java b/java/037. Sudoku Solver.java
index 3f9a5ea..c5510c5 100644
--- a/java/037. Sudoku Solver.java	
+++ b/java/037. Sudoku Solver.java	
@@ -1,67 +1,67 @@
 public class Solution {
     public void solveSudoku(char[][] board) {
-    	//true表示需要填的
+        //true表示需要填的
         boolean[][] flag=new boolean[9][9];
         for (int i = 0; i < 9; i++) {
-			for (int j = 0; j < 9; j++) {
-				flag[i][j]=board[i][j]==&#39;.&#39;;
-			}
-		}
+            for (int j = 0; j < 9; j++) {
+                flag[i][j]=board[i][j]==&#39;.&#39;;
+            }
+        }
         for (int i = 0; i < 81;) {
-			int x=i/9;
-			int y=i%9;
-			if (flag[x][y]) {
-				if (board[x][y]==&#39;.&#39;) {
-					board[x][y]=&#39;1&#39;;
-					if (f(board,x,y,board[x][y])) {
-						i++;
-					}
-				}else if(board[x][y]<&#39;9&#39;){
-					board[x][y]++;
-					if (f(board,x,y,board[x][y])) {
-						i++;
-					}
-				}else {
-					//回退
-					while ((!flag[x][y])||board[x][y]==&#39;9&#39;) {
-						if (flag[x][y]) {
-							board[x][y]=&#39;.&#39;;
-						}
-						i--;
-						if (i<0) {
-							return ;
-						}
-						x=i/9;
-						y=i%9;
-					}
-				}
-			}else {
-				i++;
-			}
-		}
+            int x=i/9;
+            int y=i%9;
+            if (flag[x][y]) {
+                if (board[x][y]==&#39;.&#39;) {
+                    board[x][y]=&#39;1&#39;;
+                    if (f(board,x,y,board[x][y])) {
+                        i++;
+                    }
+                }else if(board[x][y]<&#39;9&#39;){
+                    board[x][y]++;
+                    if (f(board,x,y,board[x][y])) {
+                        i++;
+                    }
+                }else {
+                    //回退
+                    while ((!flag[x][y])||board[x][y]==&#39;9&#39;) {
+                        if (flag[x][y]) {
+                            board[x][y]=&#39;.&#39;;
+                        }
+                        i--;
+                        if (i<0) {
+                            return ;
+                        }
+                        x=i/9;
+                        y=i%9;
+                    }
+                }
+            }else {
+                i++;
+            }
+        }
     }
     public boolean f(char[][] board,int x,int y,char val){
-    	int a=x/3;
-    	int b=y/3;
-    	for (int i = 0; i < 9; i++) {
-    		if (i!=y) {
-				if (board[x][i]==val) {
-					return false;
-				}
-			}
-    		if (x!=i) {
-				if (board[i][y]==val) {
-					return false;
-				}
-			}
-    		int ax=i/3;
-    		int by=i%3;
-    		if (x!=a*3+ax||y!=b*3+by) {
-				if (board[a*3+ax][b*3+by]==val) {
-					return false;
-				}
-			}
-		}
-    	return true;
+        int a=x/3;
+        int b=y/3;
+        for (int i = 0; i < 9; i++) {
+            if (i!=y) {
+                if (board[x][i]==val) {
+                    return false;
+                }
+            }
+            if (x!=i) {
+                if (board[i][y]==val) {
+                    return false;
+                }
+            }
+            int ax=i/3;
+            int by=i%3;
+            if (x!=a*3+ax||y!=b*3+by) {
+                if (board[a*3+ax][b*3+by]==val) {
+                    return false;
+                }
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/038. Count and Say.java b/java/038. Count and Say.java
index e310375..faa38ef 100644
--- a/java/038. Count and Say.java	
+++ b/java/038. Count and Say.java	
@@ -1,31 +1,31 @@
 public class Solution {
     public String countAndSay(int n) {
-		if (n == 1) {
-			return "1";
-		}
-		String answer = "1";
-		for (int i = 0; i < n - 1; i++) {
-			answer = new Solution().readNum(answer);
-		}
-		return answer;
-	}
+        if (n == 1) {
+            return "1";
+        }
+        String answer = "1";
+        for (int i = 0; i < n - 1; i++) {
+            answer = new Solution().readNum(answer);
+        }
+        return answer;
+    }
 
-	public String readNum(String num) {
-		int n = 1;
-		String t = num.substring(0, 1);
-		StringBuffer answer=new StringBuffer();
-		String k = "";
-		for (int i = 1; i < num.length(); i++) {
-			k = num.substring(i, i + 1);
-			if (k.equals(t)) {
-				n++;
-			} else {
-				answer=answer.append(n).append(t);
-				t = k;
-				n = 1;
-			}
-		}
-		answer = answer.append(n).append(t);
-		return answer.toString();
-	}
+    public String readNum(String num) {
+        int n = 1;
+        String t = num.substring(0, 1);
+        StringBuffer answer=new StringBuffer();
+        String k = "";
+        for (int i = 1; i < num.length(); i++) {
+            k = num.substring(i, i + 1);
+            if (k.equals(t)) {
+                n++;
+            } else {
+                answer=answer.append(n).append(t);
+                t = k;
+                n = 1;
+            }
+        }
+        answer = answer.append(n).append(t);
+        return answer.toString();
+    }
 }
\ No newline at end of file
diff --git a/java/039. Combination Sum.java b/java/039. Combination Sum.java
index 965ff88..1ef0287 100644
--- a/java/039. Combination Sum.java	
+++ b/java/039. Combination Sum.java	
@@ -1,39 +1,39 @@
 public class Solution {
     public List<List<Integer>> combinationSum(int[] candidates, int target) {
-    	Arrays.sort(candidates);
-    	return f(candidates, target, new HashMap<Integer, List<List<Integer>>>());
+        Arrays.sort(candidates);
+        return f(candidates, target, new HashMap<Integer, List<List<Integer>>>());
     }
     public List<List<Integer>> f(int[] candidates, int target,HashMap<Integer, List<List<Integer>>> map){
-    	if (map.get(target)==null) {
-    		List<List<Integer>> ans=new ArrayList<List<Integer>>();
-			if (target<candidates[0]) {
-				return ans;
-			}
-			for (int i = 0; i < candidates.length; i++) {
-				int k=candidates[i];
-				if (k<target) {
-					List<List<Integer>> list=f(candidates,target-k,map);
-					if (list!=null&&list.size()!=0) {
-						for (int j = 0; j < list.size(); j++) {
-							if (list.get(j).get(0)>=k) {
-								List<Integer> l=new ArrayList<Integer>();
-								l.add(k);
-								l.addAll(list.get(j));
-								ans.add(l);
-							}
-						}
-					}
-				}else if (k==target) {
-					List<Integer> l=new ArrayList<Integer>();
-					l.add(k);
-					ans.add(l);
-				}else {
-					break;
-				}
-			}
-			map.put(target, ans);
-			return ans;
-		}
-    	return map.get(target);
+        if (map.get(target)==null) {
+            List<List<Integer>> ans=new ArrayList<List<Integer>>();
+            if (target<candidates[0]) {
+                return ans;
+            }
+            for (int i = 0; i < candidates.length; i++) {
+                int k=candidates[i];
+                if (k<target) {
+                    List<List<Integer>> list=f(candidates,target-k,map);
+                    if (list!=null&&list.size()!=0) {
+                        for (int j = 0; j < list.size(); j++) {
+                            if (list.get(j).get(0)>=k) {
+                                List<Integer> l=new ArrayList<Integer>();
+                                l.add(k);
+                                l.addAll(list.get(j));
+                                ans.add(l);
+                            }
+                        }
+                    }
+                }else if (k==target) {
+                    List<Integer> l=new ArrayList<Integer>();
+                    l.add(k);
+                    ans.add(l);
+                }else {
+                    break;
+                }
+            }
+            map.put(target, ans);
+            return ans;
+        }
+        return map.get(target);
     }
 }
\ No newline at end of file
diff --git a/java/040. Combination Sum II.java b/java/040. Combination Sum II.java
index a3f7b90..e35e627 100644
--- a/java/040. Combination Sum II.java	
+++ b/java/040. Combination Sum II.java	
@@ -4,30 +4,30 @@ public List<List<Integer>> combinationSum2(int[] candidates, int target) {
         return f(candidates,target,candidates.length-1);
     }
     public List<List<Integer>> f(int[] candidates, int target,int l) {
-    	List<List<Integer>> ans=new ArrayList<List<Integer>>();
-    	if (candidates[0]>target||target<0||l<0) {
-			return ans;
-		}
-    	for (int i =l; i >=0 ; i--) {
-			int k=candidates[i];
-			if (k==target) {
-				List<Integer> list=new ArrayList<Integer>();
-				list.add(k);
-				ans.add(list);
-			}else {
-				List<List<Integer>> q=f(candidates,target-k,i-1);
-				if (q!=null&&q.size()!=0) {
-					for (int j = 0; j < q.size(); j++) {
-						List<Integer> list=q.get(j);
-						list.add(k);
-						ans.add(list);
-					}
-				}
-			}
-			while (i>0&&candidates[i]==candidates[i-1]) {
-				i--;
-			}
-		}
-    	return ans;
+        List<List<Integer>> ans=new ArrayList<List<Integer>>();
+        if (candidates[0]>target||target<0||l<0) {
+            return ans;
+        }
+        for (int i =l; i >=0 ; i--) {
+            int k=candidates[i];
+            if (k==target) {
+                List<Integer> list=new ArrayList<Integer>();
+                list.add(k);
+                ans.add(list);
+            }else {
+                List<List<Integer>> q=f(candidates,target-k,i-1);
+                if (q!=null&&q.size()!=0) {
+                    for (int j = 0; j < q.size(); j++) {
+                        List<Integer> list=q.get(j);
+                        list.add(k);
+                        ans.add(list);
+                    }
+                }
+            }
+            while (i>0&&candidates[i]==candidates[i-1]) {
+                i--;
+            }
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/041. First Missing Positive.java b/java/041. First Missing Positive.java
index fcc75a5..3c2d60b 100644
--- a/java/041. First Missing Positive.java	
+++ b/java/041. First Missing Positive.java	
@@ -1,21 +1,21 @@
 public class Solution {
     public int firstMissingPositive(int[] nums) {
-    	for (int i = 0; i < nums.length; i++) {
-			if (nums[i]!=i+1) {
-				if (nums[i]<=nums.length&&nums[i]>0&&nums[nums[i]-1]!=nums[i]) {
-					int k=nums[nums[i]-1];
-					nums[nums[i]-1]=nums[i];
-					nums[i]=k;
-					i--;
-				}
-			}
-		}
-    	for (int i = 0; i < nums.length; i++) {
-			if (nums[i]!=i+1) {
-				return i+1;
-			}
-		}
-    	return nums.length+1;
+        for (int i = 0; i < nums.length; i++) {
+            if (nums[i]!=i+1) {
+                if (nums[i]<=nums.length&&nums[i]>0&&nums[nums[i]-1]!=nums[i]) {
+                    int k=nums[nums[i]-1];
+                    nums[nums[i]-1]=nums[i];
+                    nums[i]=k;
+                    i--;
+                }
+            }
+        }
+        for (int i = 0; i < nums.length; i++) {
+            if (nums[i]!=i+1) {
+                return i+1;
+            }
+        }
+        return nums.length+1;
     
         
     }
diff --git a/java/042. Trapping Rain Water.java b/java/042. Trapping Rain Water.java
index c59b046..0d04929 100644
--- a/java/042. Trapping Rain Water.java	
+++ b/java/042. Trapping Rain Water.java	
@@ -1,19 +1,19 @@
 public class Solution {
         public int trap(int[] height) {
-    	if (height.length<=1) {
-			return 0;
-		}
-    	int a=0;
-    	int h=height[a];
-    	/**
-    	 * 求出最高峰
-    	 */
+        if (height.length<=1) {
+            return 0;
+        }
+        int a=0;
+        int h=height[a];
+        /**
+         * 求出最高峰
+         */
         for (int i = 1; i < height.length; i++) {
-        	if (height[i]>h) {
-				a=i;
-				h=height[i];
-			}
-		}
+            if (height[i]>h) {
+                a=i;
+                h=height[i];
+            }
+        }
         Map<String, Integer> leftMap=new HashMap<String, Integer>();
         Map<String, Integer> rightMap=new HashMap<String, Integer>();
         leftMap.put("result", 0);
@@ -22,7 +22,7 @@ public int trap(int[] height) {
         rightMap.put("a",a);
         Map<String, Integer> leftrRsult=new Solution().left(leftMap, height);
         Map<String, Integer> rightResult=new Solution().right(leftMap, height);
-    	return leftrRsult.get("result")+rightResult.get("result");
+        return leftrRsult.get("result")+rightResult.get("result");
     }
     
     /**
@@ -32,31 +32,31 @@ public int trap(int[] height) {
      * @return
      */
     public Map<String, Integer> left(Map<String, Integer> m,int[] height){
-    	Map<String, Integer> map=new HashMap<String, Integer>();
-    	if (m==null||m.get("a")==null) {
-			return m;
-		}
-    	if (m.get("a")<=1) {
-			return m;
-		}
-    	int h=height[0];
-    	int result=m.get("result");
-    	int sum=0;
-    	int a=0;
-    	for (int i = 1; i <m.get("a"); i++) {
-			if (height[i]<h) {
-				sum+=(h-height[i]);
-			}else {
-				sum=0;
-				h=height[i];
-				a=i;
-			}
-		}
-    	result+=sum;
-    	map.put("result", result);
-    	map.put("a", a);
-            	
-    	return left(map, height);
+        Map<String, Integer> map=new HashMap<String, Integer>();
+        if (m==null||m.get("a")==null) {
+            return m;
+        }
+        if (m.get("a")<=1) {
+            return m;
+        }
+        int h=height[0];
+        int result=m.get("result");
+        int sum=0;
+        int a=0;
+        for (int i = 1; i <m.get("a"); i++) {
+            if (height[i]<h) {
+                sum+=(h-height[i]);
+            }else {
+                sum=0;
+                h=height[i];
+                a=i;
+            }
+        }
+        result+=sum;
+        map.put("result", result);
+        map.put("a", a);
+                
+        return left(map, height);
     }
     /**
      * 求右侧
@@ -65,30 +65,30 @@ public Map<String, Integer> left(Map<String, Integer> m,int[] height){
      * @return
      */
     public Map<String, Integer> right(Map<String, Integer> m,int[] height){
-    	Map<String, Integer> map=new HashMap<String, Integer>();
-    	if (m==null||m.get("a")==null) {
-			return m;
-		}
-    	if (m.get("a")>=height.length-2) {
-			return m;
-		}
-    	int h=height[height.length-1];
-    	int result=m.get("result");
-    	int sum=0;
-    	int a=0;
-    	for (int i = height.length-1; i>m.get("a"); i--) {
-			if (height[i]<h) {
-				sum+=(h-height[i]);
-			}else {
-				sum=0;
-				h=height[i];
-				a=i;
-			}
-		}
-    	result+=sum;
-    	map.put("result", result);
-    	map.put("a", a);
-            	
-    	return right(map, height);
+        Map<String, Integer> map=new HashMap<String, Integer>();
+        if (m==null||m.get("a")==null) {
+            return m;
+        }
+        if (m.get("a")>=height.length-2) {
+            return m;
+        }
+        int h=height[height.length-1];
+        int result=m.get("result");
+        int sum=0;
+        int a=0;
+        for (int i = height.length-1; i>m.get("a"); i--) {
+            if (height[i]<h) {
+                sum+=(h-height[i]);
+            }else {
+                sum=0;
+                h=height[i];
+                a=i;
+            }
+        }
+        result+=sum;
+        map.put("result", result);
+        map.put("a", a);
+                
+        return right(map, height);
     }
 }
\ No newline at end of file
diff --git a/java/043. Multiply Strings.java b/java/043. Multiply Strings.java
index 49b8619..750b82a 100644
--- a/java/043. Multiply Strings.java	
+++ b/java/043. Multiply Strings.java	
@@ -1,43 +1,43 @@
 public class Solution {
     public String multiply(String num1, String num2) {
         if (num1.equals("0")||num2.equals("0")) {
-			return "0";
-		}
-    	if (num1.length()<num2.length()) {
-			return multiply(num2,num1);
-		}
-    	int l1=num1.length();
+            return "0";
+        }
+        if (num1.length()<num2.length()) {
+            return multiply(num2,num1);
+        }
+        int l1=num1.length();
         int[] n1=new int[l1];
         for (int i = 0; i <l1; i++) {
-			n1[l1-i-1]=Integer.parseInt(num1.substring(i, i+1));
-		}
+            n1[l1-i-1]=Integer.parseInt(num1.substring(i, i+1));
+        }
         int l2=num2.length();
         int[] n2=new int[l1];
         for (int i = 0; i <l2; i++) {
-			n2[l2-i-1]=Integer.parseInt(num2.substring(i, i+1));
-		}
+            n2[l2-i-1]=Integer.parseInt(num2.substring(i, i+1));
+        }
         int[] a=new int[l1+l2-1];
-    	int sum=0;
-    	int carry=0;
-		for (int i = 0; i < a.length; i++) {
-			// 每一位乘级相加的结果
-			for (int j = Math.max(0,i-l2+1); j <= Math.min(i,l1-1); j++) {
-				sum += n1[j] * n2[i-j];
-			}
-			// 加进位
-			sum += carry;
-			carry = sum / 10;
-			sum%=10;
-			a[i]=sum;
-			sum = 0;
-		}
-		StringBuffer sb=new StringBuffer();
-		if (carry!=0) {
-			sb.append(String.valueOf(carry));
-		}
-    	for (int i = a.length-1; i >=0 ; i--) {
-			sb.append(String.valueOf(a[i]));
-		}
-    	return sb.toString();
+        int sum=0;
+        int carry=0;
+        for (int i = 0; i < a.length; i++) {
+            // 每一位乘级相加的结果
+            for (int j = Math.max(0,i-l2+1); j <= Math.min(i,l1-1); j++) {
+                sum += n1[j] * n2[i-j];
+            }
+            // 加进位
+            sum += carry;
+            carry = sum / 10;
+            sum%=10;
+            a[i]=sum;
+            sum = 0;
+        }
+        StringBuffer sb=new StringBuffer();
+        if (carry!=0) {
+            sb.append(String.valueOf(carry));
+        }
+        for (int i = a.length-1; i >=0 ; i--) {
+            sb.append(String.valueOf(a[i]));
+        }
+        return sb.toString();
     }
 }
\ No newline at end of file
diff --git a/java/045. Jump Game II.java b/java/045. Jump Game II.java
index 53072d4..f5fef6a 100644
--- a/java/045. Jump Game II.java	
+++ b/java/045. Jump Game II.java	
@@ -1,25 +1,25 @@
 public class Solution {
     public int jump(int[] nums) {
-    	if (nums.length==1) {
-			return 0;
-		}
-    	int max=0;
+        if (nums.length==1) {
+            return 0;
+        }
+        int max=0;
         int[] steps=new int[nums.length];
         steps[0]=0;
         for (int i = 0; i < nums.length-1; i++) {
-			int n=nums[i];
-			if (n+i>max) {
-				int s=steps[i];
-				for (int j = max+1; j <=n+i; j++) {
-					if (j<steps.length) {
-						if (steps[j]==0||steps[j]>s+1) {
-							steps[j]=s+1;
-						}
-					}
-				}
-				max=n+i;
-			}
-		}
-    	return steps[steps.length-1];
+            int n=nums[i];
+            if (n+i>max) {
+                int s=steps[i];
+                for (int j = max+1; j <=n+i; j++) {
+                    if (j<steps.length) {
+                        if (steps[j]==0||steps[j]>s+1) {
+                            steps[j]=s+1;
+                        }
+                    }
+                }
+                max=n+i;
+            }
+        }
+        return steps[steps.length-1];
     }
 }
\ No newline at end of file
diff --git a/java/046. Permutations.java b/java/046. Permutations.java
index fd2e67d..a90d4a7 100644
--- a/java/046. Permutations.java	
+++ b/java/046. Permutations.java	
@@ -1,42 +1,42 @@
 public class Solution {
     public List<List<Integer>> permute(int[] nums) {
-		 List<List<Integer>> answerList=new ArrayList<List<Integer>>();
-	        for (int i = 0; i < nums.length; i++) {
-	        	int size=answerList.size();
-				if (size==0) {
-					for (int j = 0; j < nums.length; j++) {
-						List<Integer> intList=new ArrayList<Integer>();
-						intList.add(nums[j]);
-						answerList.add(intList);
-					}
-				}else {
-					for (int j = 0; j < size; j++) {
-						List<Integer> intList=answerList.get(j);
-						Map<Integer,String> map=new HashMap<Integer,String>();
-						for (int l = 0; l <intList.size(); l++) {
-							map.put(intList.get(l), "存在");
-						}
-						for (int k = 0; k < nums.length; k++) {
-							if (map.get(nums[k])==null) {
-								System.out.println("k="+k);
-								List<Integer> newList=new ArrayList<Integer>();
-								for (int l = 0; l < intList.size(); l++) {
-									newList.add(intList.get(l));
-								}
-								newList.add(nums[k]);
-								System.out.println();
-								answerList.add(newList);
-							}
-						}
-					}
-					if (size!=answerList.size()) {
-						for (int j = size-1; j >=0; j--) {
-							answerList.remove(j);
-						}
-					}
-				}
-			}
-		 
-		 return answerList;
-	    }
+         List<List<Integer>> answerList=new ArrayList<List<Integer>>();
+            for (int i = 0; i < nums.length; i++) {
+                int size=answerList.size();
+                if (size==0) {
+                    for (int j = 0; j < nums.length; j++) {
+                        List<Integer> intList=new ArrayList<Integer>();
+                        intList.add(nums[j]);
+                        answerList.add(intList);
+                    }
+                }else {
+                    for (int j = 0; j < size; j++) {
+                        List<Integer> intList=answerList.get(j);
+                        Map<Integer,String> map=new HashMap<Integer,String>();
+                        for (int l = 0; l <intList.size(); l++) {
+                            map.put(intList.get(l), "存在");
+                        }
+                        for (int k = 0; k < nums.length; k++) {
+                            if (map.get(nums[k])==null) {
+                                System.out.println("k="+k);
+                                List<Integer> newList=new ArrayList<Integer>();
+                                for (int l = 0; l < intList.size(); l++) {
+                                    newList.add(intList.get(l));
+                                }
+                                newList.add(nums[k]);
+                                System.out.println();
+                                answerList.add(newList);
+                            }
+                        }
+                    }
+                    if (size!=answerList.size()) {
+                        for (int j = size-1; j >=0; j--) {
+                            answerList.remove(j);
+                        }
+                    }
+                }
+            }
+         
+         return answerList;
+        }
 }
\ No newline at end of file
diff --git a/java/048. Rotate Image.java b/java/048. Rotate Image.java
index b63085e..3935343 100644
--- a/java/048. Rotate Image.java	
+++ b/java/048. Rotate Image.java	
@@ -1,14 +1,14 @@
 public class Solution {
     public void rotate(int[][] matrix) {
-    	int n=matrix.length;
+        int n=matrix.length;
         for (int i = 0; i < n/2; i++) {
-			for (int j = i; j <n-i-1; j++) {
-				int k=matrix[i][j];
-				matrix[i][j]=matrix[n-1-j][i];
-				matrix[n-1-j][i]=matrix[n-1-i][n-1-j];
-				matrix[n-1-i][n-1-j]=matrix[j][n-1-i];
-    			matrix[j][n-1-i]=k;
-			}
-		}
+            for (int j = i; j <n-i-1; j++) {
+                int k=matrix[i][j];
+                matrix[i][j]=matrix[n-1-j][i];
+                matrix[n-1-j][i]=matrix[n-1-i][n-1-j];
+                matrix[n-1-i][n-1-j]=matrix[j][n-1-i];
+                matrix[j][n-1-i]=k;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/049. Group Anagrams.java b/java/049. Group Anagrams.java
index 0b7a598..ad04dd5 100644
--- a/java/049. Group Anagrams.java	
+++ b/java/049. Group Anagrams.java	
@@ -1,34 +1,34 @@
 public class Solution {
     public List<List<String>> groupAnagrams(String[] strs) {
         Arrays.sort(strs);
-    	String[] newStrs=new String[strs.length];
+        String[] newStrs=new String[strs.length];
         for (int i = 0; i < strs.length; i++) {
-			char[] c=strs[i].toCharArray();
-			Arrays.sort(c);
-			newStrs[i]=String.valueOf(c);
-		}
+            char[] c=strs[i].toCharArray();
+            Arrays.sort(c);
+            newStrs[i]=String.valueOf(c);
+        }
         Map<String,List<Integer>> map=new HashMap<String, List<Integer>>();
         for (int i = 0; i < newStrs.length; i++) {
-			String str=newStrs[i];
-			List<Integer> list=null;
-			if (map.get(str)==null) {
-				list=new ArrayList<Integer>();
-			}else {
-				list=map.get(str);
-			}
-			list.add(i);
-			map.put(str, list);
-		}
+            String str=newStrs[i];
+            List<Integer> list=null;
+            if (map.get(str)==null) {
+                list=new ArrayList<Integer>();
+            }else {
+                list=map.get(str);
+            }
+            list.add(i);
+            map.put(str, list);
+        }
         List<List<String>> ans=new ArrayList<List<String>>();
         Set<String> keySet = map.keySet();
         for (String s:keySet) {
-        	List<Integer> l=map.get(s);
-        	List<String> list=new ArrayList<String>();
-        	for (int i = 0; i < l.size(); i++) {
-				list.add(strs[l.get(i)]);
-			}
-        	ans.add(list);
-		}
+            List<Integer> l=map.get(s);
+            List<String> list=new ArrayList<String>();
+            for (int i = 0; i < l.size(); i++) {
+                list.add(strs[l.get(i)]);
+            }
+            ans.add(list);
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/050. Pow(x, n).java b/java/050. Pow(x, n).java
index ec8305d..f4b6386 100644
--- a/java/050. Pow(x, n).java	
+++ b/java/050. Pow(x, n).java	
@@ -1,30 +1,30 @@
 public class Solution {
     public double myPow(double x, int n) {
-    	if (n==0) {
-			return 1.0;
-		}
-    	boolean flag=true;
-    	if (n<0) {
-			n=0-n;
-			flag=false;
-		}
-    	boolean slag=true;
-    	if (x<0) {
-			x=0-x;
-			if (n%2!=0) {
-				slag=false;
-			}
-		}
-    	if (x==1.0) {
-			return slag?1.0:-1.0;
-		}
-    	double answer=1.0;
+        if (n==0) {
+            return 1.0;
+        }
+        boolean flag=true;
+        if (n<0) {
+            n=0-n;
+            flag=false;
+        }
+        boolean slag=true;
+        if (x<0) {
+            x=0-x;
+            if (n%2!=0) {
+                slag=false;
+            }
+        }
+        if (x==1.0) {
+            return slag?1.0:-1.0;
+        }
+        double answer=1.0;
         for (int i = 0; i < n; i++) {
-        	answer*=x;
-        	if (answer==0.0) {
-				return answer;
-			}
-		}
-    	return flag?(slag?answer:-answer):(slag?1/answer:-1/answer);
+            answer*=x;
+            if (answer==0.0) {
+                return answer;
+            }
+        }
+        return flag?(slag?answer:-answer):(slag?1/answer:-1/answer);
     }
 }
\ No newline at end of file
diff --git a/java/051. N-Queens.java b/java/051. N-Queens.java
index 68fb17a..064b45e 100644
--- a/java/051. N-Queens.java	
+++ b/java/051. N-Queens.java	
@@ -1,66 +1,66 @@
 public class Solution {
     public List<List<String>> solveNQueens(int n) {
-    	//装n皇后的数组
-    	int[] nums=new int[n];
-    	//答案
-    	List<List<String>> ans=new ArrayList<List<String>>();
-    	int i=0;
-    	while (true) {
-    		//所有可能已经尝试完毕，退出游戏
-			if (i<0) {
-				return ans;
-			}
-			//成功尝试出一种答案， 装载答案
-			if (i==n) {
-				List<String> list=new ArrayList<String>();
-				for (int j = 0; j < nums.length; j++) {
-					StringBuffer sb=new StringBuffer();
-					for (int k = 0; k < n; k++) {
-						if (k!=nums[j]) {
-							sb.append(".");
-						}else {
-							sb.append("Q");
-						}
-					}
-					list.add(sb.toString());
-				}
-				ans.add(list);
-				//回退
-				i--;
-				while (nums[i]==n) {
-					nums[i]=0;
-					i--;
-				}
-				nums[i]++;
-			}else {
-				if (nums[i]==n) {
-					//回退
-					while (i>=0&&nums[i]==n) {
-						nums[i]=0;
-						i--;
-					}
-					if (i>=0) {
-						nums[i]++;
-					}
-				}else {
-					if (f(nums,i,nums[i])) {
-						i++;
-					}else {
-						nums[i]++;
-					}
-				}
-			}
-			
-		}
-//    	return ans;
+        //装n皇后的数组
+        int[] nums=new int[n];
+        //答案
+        List<List<String>> ans=new ArrayList<List<String>>();
+        int i=0;
+        while (true) {
+            //所有可能已经尝试完毕，退出游戏
+            if (i<0) {
+                return ans;
+            }
+            //成功尝试出一种答案， 装载答案
+            if (i==n) {
+                List<String> list=new ArrayList<String>();
+                for (int j = 0; j < nums.length; j++) {
+                    StringBuffer sb=new StringBuffer();
+                    for (int k = 0; k < n; k++) {
+                        if (k!=nums[j]) {
+                            sb.append(".");
+                        }else {
+                            sb.append("Q");
+                        }
+                    }
+                    list.add(sb.toString());
+                }
+                ans.add(list);
+                //回退
+                i--;
+                while (nums[i]==n) {
+                    nums[i]=0;
+                    i--;
+                }
+                nums[i]++;
+            }else {
+                if (nums[i]==n) {
+                    //回退
+                    while (i>=0&&nums[i]==n) {
+                        nums[i]=0;
+                        i--;
+                    }
+                    if (i>=0) {
+                        nums[i]++;
+                    }
+                }else {
+                    if (f(nums,i,nums[i])) {
+                        i++;
+                    }else {
+                        nums[i]++;
+                    }
+                }
+            }
+            
+        }
+//        return ans;
     }
     public boolean f(int[] nums,int x,int val){
-    	for (int i = 0; i < x; i++) {
-    		int t=x-i;
-			if (val==nums[i]||val==nums[i]+t||val==nums[i]-t) {
-				return false;
-			}
-		}
-    	return true;
+        for (int i = 0; i < x; i++) {
+            int t=x-i;
+            if (val==nums[i]||val==nums[i]+t||val==nums[i]-t) {
+                return false;
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/052. N-Queens II.java b/java/052. N-Queens II.java
index 02dafcb..e6c3f42 100644
--- a/java/052. N-Queens II.java	
+++ b/java/052. N-Queens II.java	
@@ -4,67 +4,67 @@ public int totalNQueens(int n) {
     }
     
     public List<List<String>> solveNQueens(int n) {
-    	//װn�ʺ������
-    	int[] nums=new int[n];
-    	//��
-    	List<List<String>> ans=new ArrayList<List<String>>();
-    	int i=0;
-    	while (true) {
-    		//���п����Ѿ�������ϣ��˳���Ϸ
-			if (i<0) {
-				return ans;
-			}
-			//�ɹ����Գ�һ�ִ𰸣� װ�ش�
-			if (i==n) {
-				List<String> list=new ArrayList<String>();
-				for (int j = 0; j < nums.length; j++) {
-					StringBuffer sb=new StringBuffer();
-					for (int k = 0; k < n; k++) {
-						if (k!=nums[j]) {
-							sb.append(".");
-						}else {
-							sb.append("Q");
-						}
-					}
-					list.add(sb.toString());
-				}
-				ans.add(list);
-				//����
-				i--;
-				while (nums[i]==n) {
-					nums[i]=0;
-					i--;
-				}
-				nums[i]++;
-			}else {
-				if (nums[i]==n) {
-					//����
-					while (i>=0&&nums[i]==n) {
-						nums[i]=0;
-						i--;
-					}
-					if (i>=0) {
-						nums[i]++;
-					}
-				}else {
-					if (f(nums,i,nums[i])) {
-						i++;
-					}else {
-						nums[i]++;
-					}
-				}
-			}
-			
-		}
-//    	return ans;
+        //װn�ʺ������
+        int[] nums=new int[n];
+        //��
+        List<List<String>> ans=new ArrayList<List<String>>();
+        int i=0;
+        while (true) {
+            //���п����Ѿ�������ϣ��˳���Ϸ
+            if (i<0) {
+                return ans;
+            }
+            //�ɹ����Գ�һ�ִ𰸣� װ�ش�
+            if (i==n) {
+                List<String> list=new ArrayList<String>();
+                for (int j = 0; j < nums.length; j++) {
+                    StringBuffer sb=new StringBuffer();
+                    for (int k = 0; k < n; k++) {
+                        if (k!=nums[j]) {
+                            sb.append(".");
+                        }else {
+                            sb.append("Q");
+                        }
+                    }
+                    list.add(sb.toString());
+                }
+                ans.add(list);
+                //����
+                i--;
+                while (nums[i]==n) {
+                    nums[i]=0;
+                    i--;
+                }
+                nums[i]++;
+            }else {
+                if (nums[i]==n) {
+                    //����
+                    while (i>=0&&nums[i]==n) {
+                        nums[i]=0;
+                        i--;
+                    }
+                    if (i>=0) {
+                        nums[i]++;
+                    }
+                }else {
+                    if (f(nums,i,nums[i])) {
+                        i++;
+                    }else {
+                        nums[i]++;
+                    }
+                }
+            }
+            
+        }
+//        return ans;
     }
     public boolean f(int[] nums,int x,int val){
-    	for (int i = 0; i < x; i++) {
-    		int t=x-i;
-			if (val==nums[i]||val==nums[i]+t||val==nums[i]-t) {
-				return false;
-			}
-		}
-    	return true;
+        for (int i = 0; i < x; i++) {
+            int t=x-i;
+            if (val==nums[i]||val==nums[i]+t||val==nums[i]-t) {
+                return false;
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/053. Maximum Subarray.java b/java/053. Maximum Subarray.java
index 3f34e7d..7470ba0 100644
--- a/java/053. Maximum Subarray.java	
+++ b/java/053. Maximum Subarray.java	
@@ -3,14 +3,14 @@ public int maxSubArray(int[] nums) {
         int sum=0;
         int answer=nums[0];
         for (int i = 0; i < nums.length; i++) {
-			sum+=nums[i];
-			if (sum>answer) {
-				answer=sum;
-			}
-			if (sum<0) {
-				sum=0;
-			}
-		}
-    	return answer;
+            sum+=nums[i];
+            if (sum>answer) {
+                answer=sum;
+            }
+            if (sum<0) {
+                sum=0;
+            }
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/054. Spiral Matrix.java b/java/054. Spiral Matrix.java
index 6565bb3..85acfd8 100644
--- a/java/054. Spiral Matrix.java	
+++ b/java/054. Spiral Matrix.java	
@@ -1,59 +1,59 @@
 public class Solution {
     public List<Integer> spiralOrder(int[][] matrix) {
-    	List<Integer> list=new ArrayList<Integer>();
-    	//m:行，n列
-    	int mb=0;
-    	int nb=0;
+        List<Integer> list=new ArrayList<Integer>();
+        //m:行，n列
+        int mb=0;
+        int nb=0;
         int me=matrix.length;
         if (me==0) {
-			return list;
-		}
+            return list;
+        }
         int ne=matrix[0].length;
-    	while (true) {
-    		list=new Solution().right(matrix, mb, nb, me, ne, list);
-			mb++;
-			if (nb>ne-1||mb>me-1) {
-				return list;
-			}
-			list=new Solution().low(matrix, mb, nb, me, ne, list);
-			ne--;
-			if (nb>ne-1||mb>me-1) {
-				return list;
-			}
-			list=new Solution().left(matrix, mb, nb, me, ne, list);
-			me--;
-			if (nb>ne-1||mb>me-1) {
-				return list;
-			}
-			list=new Solution().up(matrix, mb, nb, me, ne, list);
-			nb++;
-			if (nb>ne-1||mb>me-1) {
-				return list;
-			}
-		}
+        while (true) {
+            list=new Solution().right(matrix, mb, nb, me, ne, list);
+            mb++;
+            if (nb>ne-1||mb>me-1) {
+                return list;
+            }
+            list=new Solution().low(matrix, mb, nb, me, ne, list);
+            ne--;
+            if (nb>ne-1||mb>me-1) {
+                return list;
+            }
+            list=new Solution().left(matrix, mb, nb, me, ne, list);
+            me--;
+            if (nb>ne-1||mb>me-1) {
+                return list;
+            }
+            list=new Solution().up(matrix, mb, nb, me, ne, list);
+            nb++;
+            if (nb>ne-1||mb>me-1) {
+                return list;
+            }
+        }
     }
     public List<Integer> right(int[][] matrix,int mb,int nb,int me,int ne,List<Integer> list){
-    	for (int i = nb; i < ne; i++) {
-			list.add(matrix[mb][i]);
-		}
-    	return list;
+        for (int i = nb; i < ne; i++) {
+            list.add(matrix[mb][i]);
+        }
+        return list;
     }
     public List<Integer> left(int[][] matrix,int mb,int nb,int me,int ne,List<Integer> list){
-    	for (int i = ne-1; i >=nb; i--) {
-			list.add(matrix[me-1][i]);
-		}
-    	return list;
+        for (int i = ne-1; i >=nb; i--) {
+            list.add(matrix[me-1][i]);
+        }
+        return list;
     }
     public List<Integer> low(int[][] matrix,int mb,int nb,int me,int ne,List<Integer> list){
-    	for (int i = mb; i < me; i++) {
-			list.add(matrix[i][ne-1]);
-		}
-    	return list;
+        for (int i = mb; i < me; i++) {
+            list.add(matrix[i][ne-1]);
+        }
+        return list;
     }
     public List<Integer> up(int[][] matrix,int mb,int nb,int me,int ne,List<Integer> list){
-    	for (int i = me-1; i >=mb; i--) {
-			list.add(matrix[i][nb]);
-		}
-    	return list;
+        for (int i = me-1; i >=mb; i--) {
+            list.add(matrix[i][nb]);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/055. Jump Game.java b/java/055. Jump Game.java
index 2b1834a..7e0ae78 100644
--- a/java/055. Jump Game.java	
+++ b/java/055. Jump Game.java	
@@ -1,25 +1,25 @@
 public class Solution {
     public boolean canJump(int[] nums) {
-    	int k=-1;
-    	int tar=-1;
+        int k=-1;
+        int tar=-1;
         for (int i = nums.length-1; i>=0 ; i--) {
-			if (k==-1&&nums[i]==0) {
-				k=0;
-				tar=i;
-			}
-			if (k==0) {
-			    if(tar==nums.length-1&&nums[i]>=tar-i){
-			        k=-1;
-			    }
-				if (nums[i]>tar-i) {
-					k=-1;
-				}
-			}
-		}
-    	if (k==-1) {
-			return true;
-		}else {
-			return false;
-		}
+            if (k==-1&&nums[i]==0) {
+                k=0;
+                tar=i;
+            }
+            if (k==0) {
+                if(tar==nums.length-1&&nums[i]>=tar-i){
+                    k=-1;
+                }
+                if (nums[i]>tar-i) {
+                    k=-1;
+                }
+            }
+        }
+        if (k==-1) {
+            return true;
+        }else {
+            return false;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/056. Merge Intervals.java b/java/056. Merge Intervals.java
index 551da01..0287b27 100644
--- a/java/056. Merge Intervals.java	
+++ b/java/056. Merge Intervals.java	
@@ -9,60 +9,60 @@
  */
 public class Solution {
     public List<Interval> merge(List<Interval> intervals) {
-    	//0开头，2结束，-1原地，1正常
-    	Map<Integer, Integer> map=new HashMap<Integer, Integer>();
-    	int sum=0;
+        //0开头，2结束，-1原地，1正常
+        Map<Integer, Integer> map=new HashMap<Integer, Integer>();
+        int sum=0;
         for (int i = 0; i <intervals.size(); i++) {
-			int s=intervals.get(i).start;
-			int e=intervals.get(i).end;
-			if (e>sum) {
-				sum=e;
-			}
-			if (s==e) {
-				if (map.get(s)==null) {
-					map.put(s, -1);
-				}
-			}else {
-				for (int j = s; j <=e; j++) {
-					if (j==s) {
-						if(map.get(j)==null||map.get(j)==-1||map.get(j)==0){
-							map.put(j, 0);
-						}else {
-							map.put(j, 1);
-						}
-					}else if (j==e) {
-						if (map.get(j)==null||map.get(j)==-1||map.get(j)==2) {
-							map.put(j, 2);
-						}else {
-							map.put(j, 1);
-						}
-					}else {
-						map.put(j, 1);
-					}
-				}
-			}
-		}
+            int s=intervals.get(i).start;
+            int e=intervals.get(i).end;
+            if (e>sum) {
+                sum=e;
+            }
+            if (s==e) {
+                if (map.get(s)==null) {
+                    map.put(s, -1);
+                }
+            }else {
+                for (int j = s; j <=e; j++) {
+                    if (j==s) {
+                        if(map.get(j)==null||map.get(j)==-1||map.get(j)==0){
+                            map.put(j, 0);
+                        }else {
+                            map.put(j, 1);
+                        }
+                    }else if (j==e) {
+                        if (map.get(j)==null||map.get(j)==-1||map.get(j)==2) {
+                            map.put(j, 2);
+                        }else {
+                            map.put(j, 1);
+                        }
+                    }else {
+                        map.put(j, 1);
+                    }
+                }
+            }
+        }
         boolean flag=true;
         List<Interval> answerList=new ArrayList<Interval>();
         int s=0;
         int e=0;
         for (int i = 0; i <sum+2; i++) {
-			if (flag) {
-				if (map.get(i)!=null&&map.get(i)==-1) {
-					answerList.add(new Interval(i,i));
-				}else if (map.get(i)!=null) {
-					s=i;
-					flag=false;
-				}
-			}else {
-				if (map.get(i)==null||map.get(i)==2) {
-					flag=true;
-					e=i;
-					answerList.add(new Interval(s,e));
-					s=0;
-				}
-			}
-		}
-    	return answerList;
+            if (flag) {
+                if (map.get(i)!=null&&map.get(i)==-1) {
+                    answerList.add(new Interval(i,i));
+                }else if (map.get(i)!=null) {
+                    s=i;
+                    flag=false;
+                }
+            }else {
+                if (map.get(i)==null||map.get(i)==2) {
+                    flag=true;
+                    e=i;
+                    answerList.add(new Interval(s,e));
+                    s=0;
+                }
+            }
+        }
+        return answerList;
     }
 }
\ No newline at end of file
diff --git a/java/057. Insert Interval.java b/java/057. Insert Interval.java
index eef61cc..45e234a 100644
--- a/java/057. Insert Interval.java	
+++ b/java/057. Insert Interval.java	
@@ -9,62 +9,62 @@
  */
 public class Solution {
     public List<Interval> insert(List<Interval> intervals, Interval newInterval) {
-		int s = newInterval.start;
-		int e = newInterval.end;
-		if (intervals.size()==0) {
-			intervals.add(newInterval);
-			return intervals;
-		}
-		List<Interval> answerList = new ArrayList<Interval>();
-		int ns=0;
-		int ne=0;
-		boolean beginFlag=true;
-		boolean endFlag=true;
-		for (int i = 0; i < intervals.size(); i++) {
-			if (endFlag&&beginFlag) {
-				if (intervals.get(i).start>=s) {
-					ns=s;
-					beginFlag=false;
-				}else if (intervals.get(i).end>=s) {
-					if (intervals.get(i).end>=e) {
-						endFlag=false;
-					}else {
-						ns=intervals.get(i).start;
-						beginFlag=false;
-					}
-				}
-			}
-			if (endFlag&&!beginFlag) {
-				if (intervals.get(i).start>e) {
-					ne=e;
-					answerList.add(new Interval(ns,ne));
-					endFlag=false;
-					beginFlag=true;
-				}else if(intervals.get(i).start==e){
-					ne=intervals.get(i).end;
-					answerList.add(new Interval(ns,ne));
-					endFlag=false;
-					beginFlag=true;
-					continue;
-				}else if(intervals.get(i).end>=e){
-					ne=intervals.get(i).end;
-					answerList.add(new Interval(ns,ne));
-					endFlag=false;
-					beginFlag=true;
-					continue;
-				}else if(i==intervals.size()-1){
-					ne=e;
-					answerList.add(new Interval(ns,ne));
-					return answerList;
-				}
-			}
-			if (beginFlag) {
-				answerList.add(intervals.get(i));
-			}
-		}
-		if (endFlag) {
-			answerList.add(newInterval);
-		}
-		return answerList;
-	}
+        int s = newInterval.start;
+        int e = newInterval.end;
+        if (intervals.size()==0) {
+            intervals.add(newInterval);
+            return intervals;
+        }
+        List<Interval> answerList = new ArrayList<Interval>();
+        int ns=0;
+        int ne=0;
+        boolean beginFlag=true;
+        boolean endFlag=true;
+        for (int i = 0; i < intervals.size(); i++) {
+            if (endFlag&&beginFlag) {
+                if (intervals.get(i).start>=s) {
+                    ns=s;
+                    beginFlag=false;
+                }else if (intervals.get(i).end>=s) {
+                    if (intervals.get(i).end>=e) {
+                        endFlag=false;
+                    }else {
+                        ns=intervals.get(i).start;
+                        beginFlag=false;
+                    }
+                }
+            }
+            if (endFlag&&!beginFlag) {
+                if (intervals.get(i).start>e) {
+                    ne=e;
+                    answerList.add(new Interval(ns,ne));
+                    endFlag=false;
+                    beginFlag=true;
+                }else if(intervals.get(i).start==e){
+                    ne=intervals.get(i).end;
+                    answerList.add(new Interval(ns,ne));
+                    endFlag=false;
+                    beginFlag=true;
+                    continue;
+                }else if(intervals.get(i).end>=e){
+                    ne=intervals.get(i).end;
+                    answerList.add(new Interval(ns,ne));
+                    endFlag=false;
+                    beginFlag=true;
+                    continue;
+                }else if(i==intervals.size()-1){
+                    ne=e;
+                    answerList.add(new Interval(ns,ne));
+                    return answerList;
+                }
+            }
+            if (beginFlag) {
+                answerList.add(intervals.get(i));
+            }
+        }
+        if (endFlag) {
+            answerList.add(newInterval);
+        }
+        return answerList;
+    }
 }
\ No newline at end of file
diff --git a/java/058. Length of Last Word.java b/java/058. Length of Last Word.java
index c256f79..29f442c 100644
--- a/java/058. Length of Last Word.java	
+++ b/java/058. Length of Last Word.java	
@@ -1,25 +1,25 @@
 public class Solution {
     public int lengthOfLastWord(String s) {
         if (s.length()==0) {
-			return 0;
-		}
+            return 0;
+        }
         int e=-1;
         for (int i = s.length()-1; i >=0; i--) {
-			if (!s.substring(i,i+1).equals(" ")) {
-				e=i;
-				break;
-			}
-		}
+            if (!s.substring(i,i+1).equals(" ")) {
+                e=i;
+                break;
+            }
+        }
         if (e==-1) {
-			return 0;
-		}
+            return 0;
+        }
         int b=-1;
         for (int i = e-1; i >=0; i--) {
-			if (s.substring(i,i+1).equals(" ")) {
-				b=i;
-				break;
-			}
-		}
+            if (s.substring(i,i+1).equals(" ")) {
+                b=i;
+                break;
+            }
+        }
         System.out.println("b="+b);
         return b==-1?e+1:e-b;
     }
diff --git a/java/059. Spiral Matrix II.java b/java/059. Spiral Matrix II.java
index 67401c7..19a021a 100644
--- a/java/059. Spiral Matrix II.java	
+++ b/java/059. Spiral Matrix II.java	
@@ -1,53 +1,53 @@
 public class Solution {
     public int[][] generateMatrix(int n) {
-		int[][] answer = new int[n][n];
-		// 顶部
-		int t = 0;
-		// 底部
-		int b = n - 1;
-		// 左边
-		int l = 0;
-		// 右边
-		int r = n - 1;
-		int a = 1;
-		while (true) {
-			// 左
-			for (int i = l; i <= r; i++) {
-				answer[t][i] = a;
-				a++;
-			}
-			t++;
-			if (t > b) {
-				return answer;
-			}
-			// 下
-			for (int i = t; i <= b; i++) {
-				answer[i][r] = a;
-				a++;
-			}
-			r--;
-			if (l > r) {
-				return answer;
-			}
-			// 右
-			for (int i = r; i >= l; i--) {
-				answer[b][i] = a;
-				a++;
-			}
-			b--;
-			if (t > b) {
-				return answer;
-			}
-			// 上
-			for (int i = b; i >= t; i--) {
-				answer[i][l] = a;
-				a++;
-			}
-			l++;
-			if (l > r) {
-				return answer;
-			}
+        int[][] answer = new int[n][n];
+        // 顶部
+        int t = 0;
+        // 底部
+        int b = n - 1;
+        // 左边
+        int l = 0;
+        // 右边
+        int r = n - 1;
+        int a = 1;
+        while (true) {
+            // 左
+            for (int i = l; i <= r; i++) {
+                answer[t][i] = a;
+                a++;
+            }
+            t++;
+            if (t > b) {
+                return answer;
+            }
+            // 下
+            for (int i = t; i <= b; i++) {
+                answer[i][r] = a;
+                a++;
+            }
+            r--;
+            if (l > r) {
+                return answer;
+            }
+            // 右
+            for (int i = r; i >= l; i--) {
+                answer[b][i] = a;
+                a++;
+            }
+            b--;
+            if (t > b) {
+                return answer;
+            }
+            // 上
+            for (int i = b; i >= t; i--) {
+                answer[i][l] = a;
+                a++;
+            }
+            l++;
+            if (l > r) {
+                return answer;
+            }
 
-		}
-	}
+        }
+    }
 }
\ No newline at end of file
diff --git a/java/060. Permutation Sequence.java b/java/060. Permutation Sequence.java
index 69cea79..520d066 100644
--- a/java/060. Permutation Sequence.java	
+++ b/java/060. Permutation Sequence.java	
@@ -3,20 +3,20 @@ public String getPermutation(int n, int k) {
         int s=1;
         List<Integer> list=new ArrayList<Integer>();
         for (int i = 0; i <n; i++) {
-			list.add(i+1);
-		}
+            list.add(i+1);
+        }
         for (int i = 1; i <n; i++) {
-			s*=i;
-		}
+            s*=i;
+        }
         int t=n-1;
         StringBuffer answer=new StringBuffer();
         for (;t!=0;) {
-			answer.append(list.get((k-1)/s));
-			list.remove((k-1)/s);
-			k-=((k-1)/s*s);
-			s/=t;
-			t--;
-		}
+            answer.append(list.get((k-1)/s));
+            list.remove((k-1)/s);
+            k-=((k-1)/s*s);
+            s/=t;
+            t--;
+        }
         return answer.append(list.get(0)).toString();
     }
 }
\ No newline at end of file
diff --git a/java/061. Rotate List.java b/java/061. Rotate List.java
index f2c539e..c89373d 100644
--- a/java/061. Rotate List.java	
+++ b/java/061. Rotate List.java	
@@ -8,21 +8,21 @@
  */
 public class Solution {
     public ListNode rotateRight(ListNode head, int k) {
-    	if (head==null) {
-			return head;
-		}
+        if (head==null) {
+            return head;
+        }
         ListNode l=head;
         List<ListNode> list=new ArrayList<ListNode>();
         while (l!=null) {
-			list.add(l);
-			l=l.next;
-		}
+            list.add(l);
+            l=l.next;
+        }
         k=k%list.size();
         if (k==0) {
-			return head;
-		}
+            return head;
+        }
         list.get(list.size()-k-1).next=null;
         list.get(list.size()-1).next=head;
-    	return list.get(list.size()-k);
+        return list.get(list.size()-k);
     }
 }
\ No newline at end of file
diff --git a/java/062. Unique Paths.java b/java/062. Unique Paths.java
index eb70744..69c9909 100644
--- a/java/062. Unique Paths.java	
+++ b/java/062. Unique Paths.java	
@@ -1,30 +1,30 @@
 public class Solution {
     public int uniquePaths(int m, int n) {
-    	if (m==1||n==1) {
-			return 1;
-		}
-    	Map<Integer,Integer> map=new HashMap<Integer, Integer>();
-    	for (int i = 0; i < m; i++) {
-			map.put(i, 1);
-		}
-    	for (int i = 1; i < n-1; i++) {
-    		int sum=0;
-			for (int j = m-1; j >=0; j--) {
-				sum+=map.get(j);
-			}
-			int k=map.get(m-1);
-			for (int j = m-1; j >=0; j--) {
-				map.put(j, sum);
-				sum-=k;
-				if (j>1) {
-					k=map.get(j-1);
-				}
-			}
-		}
-    	int sum=0;
-    	for (int i = 0; i < m; i++) {
-			sum+=map.get(i);
-		}
-    	return sum;
+        if (m==1||n==1) {
+            return 1;
+        }
+        Map<Integer,Integer> map=new HashMap<Integer, Integer>();
+        for (int i = 0; i < m; i++) {
+            map.put(i, 1);
+        }
+        for (int i = 1; i < n-1; i++) {
+            int sum=0;
+            for (int j = m-1; j >=0; j--) {
+                sum+=map.get(j);
+            }
+            int k=map.get(m-1);
+            for (int j = m-1; j >=0; j--) {
+                map.put(j, sum);
+                sum-=k;
+                if (j>1) {
+                    k=map.get(j-1);
+                }
+            }
+        }
+        int sum=0;
+        for (int i = 0; i < m; i++) {
+            sum+=map.get(i);
+        }
+        return sum;
     }
 }
\ No newline at end of file
diff --git a/java/063. Unique Paths II.java b/java/063. Unique Paths II.java
index 8faaecd..7b4cc98 100644
--- a/java/063. Unique Paths II.java	
+++ b/java/063. Unique Paths II.java	
@@ -1,23 +1,23 @@
 public class Solution {
     public int uniquePathsWithObstacles(int[][] obstacleGrid) {
-    	if (obstacleGrid[0][0]==1||obstacleGrid[obstacleGrid.length-1][obstacleGrid[0].length-1]==1) {
-			return 0;
-		}
-    	Map<String,Integer> map=new HashMap<String, Integer>();
-    	return f(obstacleGrid,0,0,obstacleGrid.length-1,obstacleGrid[0].length-1,map);
+        if (obstacleGrid[0][0]==1||obstacleGrid[obstacleGrid.length-1][obstacleGrid[0].length-1]==1) {
+            return 0;
+        }
+        Map<String,Integer> map=new HashMap<String, Integer>();
+        return f(obstacleGrid,0,0,obstacleGrid.length-1,obstacleGrid[0].length-1,map);
     }
     public int f(int[][] obstacleGrid,int x,int y,int xl,int yl,Map<String,Integer> map){
-    	String coordinate=x+","+y;
-    	if (x==xl&&y==yl) {
-			return 1;
-		}
-    	if (map.get(coordinate)==null) {
-			boolean xflag=(x<xl)&&(obstacleGrid[x+1][y]==0);
-			boolean yflag=(y<yl)&&(obstacleGrid[x][y+1]==0);
-			int value=(xflag?f(obstacleGrid,x+1,y,xl,yl,map):0)+(yflag?f(obstacleGrid,x,y+1,xl,yl,map):0);
-			map.put(coordinate, value);
-			return value;
-		}
-    	return map.get(coordinate);
+        String coordinate=x+","+y;
+        if (x==xl&&y==yl) {
+            return 1;
+        }
+        if (map.get(coordinate)==null) {
+            boolean xflag=(x<xl)&&(obstacleGrid[x+1][y]==0);
+            boolean yflag=(y<yl)&&(obstacleGrid[x][y+1]==0);
+            int value=(xflag?f(obstacleGrid,x+1,y,xl,yl,map):0)+(yflag?f(obstacleGrid,x,y+1,xl,yl,map):0);
+            map.put(coordinate, value);
+            return value;
+        }
+        return map.get(coordinate);
     }
 }
\ No newline at end of file
diff --git a/java/064. Minimum Path Sum.java b/java/064. Minimum Path Sum.java
index 1805786..07e2cf9 100644
--- a/java/064. Minimum Path Sum.java	
+++ b/java/064. Minimum Path Sum.java	
@@ -1,33 +1,33 @@
 public class Solution {
     public int minPathSum(int[][] grid) {
-    	int xl=grid.length;
-    	int yl=grid[0].length;
-    	Map<String, Integer> map=new HashMap<String, Integer>();
-    	return f(grid,0,0,xl,yl,map);
+        int xl=grid.length;
+        int yl=grid[0].length;
+        Map<String, Integer> map=new HashMap<String, Integer>();
+        return f(grid,0,0,xl,yl,map);
     }
     public int f(int[][] grid,int x,int y,int xl,int yl,Map<String, Integer> map){
-    	String coordinate=x+","+y;
-    	if (map.get(coordinate)==null) {
-			if (x>=xl||y>=yl) {
-				return -1;
-			}else {
-				int xv=f(grid,x+1,y,xl,yl,map);
-				int yv=f(grid,x,y+1,xl,yl,map);
-			   int v=0;
-			   if (xv<0) {
-					v=yv;
-				}else if (yv<0) {
-					v=xv;
-				}else if (xv>yv){
-					v=yv;
-				}else {
-					v=xv;
-				}
-				int value=grid[x][y]+(v<0?0:v);
-				map.put(coordinate, value);
-				return value;
-			}
-		}
-    	return map.get(coordinate);
+        String coordinate=x+","+y;
+        if (map.get(coordinate)==null) {
+            if (x>=xl||y>=yl) {
+                return -1;
+            }else {
+                int xv=f(grid,x+1,y,xl,yl,map);
+                int yv=f(grid,x,y+1,xl,yl,map);
+               int v=0;
+               if (xv<0) {
+                    v=yv;
+                }else if (yv<0) {
+                    v=xv;
+                }else if (xv>yv){
+                    v=yv;
+                }else {
+                    v=xv;
+                }
+                int value=grid[x][y]+(v<0?0:v);
+                map.put(coordinate, value);
+                return value;
+            }
+        }
+        return map.get(coordinate);
     }
 }
diff --git a/java/066. Plus One.java b/java/066. Plus One.java
index 093ca22..aaacf4e 100644
--- a/java/066. Plus One.java	
+++ b/java/066. Plus One.java	
@@ -1,23 +1,23 @@
 public class Solution {
     public int[] plusOne(int[] digits) {
-    	int i=digits.length-1;
+        int i=digits.length-1;
         boolean flag= false;
         do {
-			if (digits[i]<9) {
-				digits[i]+=1;
-				flag=false;
-			}else {
-				digits[i]=0;
-				flag=true;
-			}
-			i--;
-		} while (flag&&i>=0);
+            if (digits[i]<9) {
+                digits[i]+=1;
+                flag=false;
+            }else {
+                digits[i]=0;
+                flag=true;
+            }
+            i--;
+        } while (flag&&i>=0);
         if (flag) {
-			int[] answer=new int[digits.length+1];
-			answer[0]=1;
-			return answer;
-		}else {
-			return digits;
-		}
+            int[] answer=new int[digits.length+1];
+            answer[0]=1;
+            return answer;
+        }else {
+            return digits;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/067. Add Binary.java b/java/067. Add Binary.java
index 298ac1c..0fbb96d 100644
--- a/java/067. Add Binary.java	
+++ b/java/067. Add Binary.java	
@@ -1,43 +1,43 @@
 public class Solution {
     public String addBinary(String a, String b) {
         if (a.equals("0")) {
-			return b;
-		}
-    	if (b.equals("0")) {
-			return a;
-		}
-    	if (a.length()<b.length()) {
-			return new Solution().addBinary(b, a);
-		}
-    	int[] ia=new int[a.length()];
-    	for (int i = a.length()-1; i >=0; i--) {
-			ia[a.length()-1-i]=Integer.parseInt(a.substring(i, i+1));
-		}
-    	int[] ib=new int[b.length()];
-    	for (int i = b.length()-1; i >=0; i--) {
-			ib[b.length()-1-i]=Integer.parseInt(b.substring(i, i+1));
-		}
-    	int target=0;
-    	int[] ias=new int[a.length()];
-    	for (int i = 0; i < ia.length; i++) {
-    		int k=0;
-			if (i<ib.length) {
-				k=ia[i]+ib[i]+target;
-				ias[i]=k%2;
-				target=k/2;
-			}else {
-				k=ia[i]+target;
-				ias[i]=k%2;
-				target=k/2;
-			}
-		}
-    	StringBuffer sb=new StringBuffer();
-    	if (target==1) {
-			sb.append("1");
-		}
-    	for (int i = ias.length-1; i >=0 ; i--) {
-			sb.append(""+ias[i]);
-		}
-    	return sb.toString();
+            return b;
+        }
+        if (b.equals("0")) {
+            return a;
+        }
+        if (a.length()<b.length()) {
+            return new Solution().addBinary(b, a);
+        }
+        int[] ia=new int[a.length()];
+        for (int i = a.length()-1; i >=0; i--) {
+            ia[a.length()-1-i]=Integer.parseInt(a.substring(i, i+1));
+        }
+        int[] ib=new int[b.length()];
+        for (int i = b.length()-1; i >=0; i--) {
+            ib[b.length()-1-i]=Integer.parseInt(b.substring(i, i+1));
+        }
+        int target=0;
+        int[] ias=new int[a.length()];
+        for (int i = 0; i < ia.length; i++) {
+            int k=0;
+            if (i<ib.length) {
+                k=ia[i]+ib[i]+target;
+                ias[i]=k%2;
+                target=k/2;
+            }else {
+                k=ia[i]+target;
+                ias[i]=k%2;
+                target=k/2;
+            }
+        }
+        StringBuffer sb=new StringBuffer();
+        if (target==1) {
+            sb.append("1");
+        }
+        for (int i = ias.length-1; i >=0 ; i--) {
+            sb.append(""+ias[i]);
+        }
+        return sb.toString();
     }
 }
\ No newline at end of file
diff --git a/java/068. Text Justification.java b/java/068. Text Justification.java
index 1179b63..d518019 100644
--- a/java/068. Text Justification.java	
+++ b/java/068. Text Justification.java	
@@ -5,66 +5,66 @@ public List<String> fullJustify(String[] words, int maxWidth) {
         List<String> list=new ArrayList<String>();
         //分行
         for (int i = 0; i < words.length; i++) {
-			if (words[i].length()<=length) {
-				list.add(words[i]);
-				length-=(words[i].length()+1);
-			}else {
-				sumList.add(list);
-				list=new ArrayList<String>();
-				length=maxWidth;
-				i--;
-			}
-		}
+            if (words[i].length()<=length) {
+                list.add(words[i]);
+                length-=(words[i].length()+1);
+            }else {
+                sumList.add(list);
+                list=new ArrayList<String>();
+                length=maxWidth;
+                i--;
+            }
+        }
         if (list.size()!=0) {
-			sumList.add(list);
-		}
+            sumList.add(list);
+        }
         List<String> ans=new ArrayList<String>();
         //处理每行的字符串
         for (int i = 0; i < sumList.size()-1; i++) {
-			List<String> l=sumList.get(i);
-			//区分一行只有一个字符串的和多个字符串的情况
-			if (l.size()==1) {
-				StringBuffer sb=new StringBuffer();
-				sb.append(l.get(0));
-				for (int j = 0; j < maxWidth-l.get(0).length(); j++) {
-					sb.append(" ");
-				}
-				System.out.println("sb.toString()="+sb.toString());
-				ans.add(sb.toString());
-			}else {
-				int totalSpace=maxWidth;
-				for (int j = 0; j < l.size(); j++) {
-					totalSpace-=l.get(j).length();
-				}
-				int eachSpace=totalSpace/(l.size()-1);
-				int extraSpace=totalSpace-eachSpace*(l.size()-1);
-				StringBuffer sb=new StringBuffer();
-				for (int j = 0; j < l.size()-1; j++) {
-					sb.append(l.get(j));
-					for (int k = 0; k < eachSpace; k++) {
-						sb.append(" ");
-					}
-					if (j<extraSpace) {
-						sb.append(" ");
-					}
-				}
-				sb.append(l.get(l.size()-1));
-				ans.add(sb.toString());
-			}
-		}
-		//处理最后一行
+            List<String> l=sumList.get(i);
+            //区分一行只有一个字符串的和多个字符串的情况
+            if (l.size()==1) {
+                StringBuffer sb=new StringBuffer();
+                sb.append(l.get(0));
+                for (int j = 0; j < maxWidth-l.get(0).length(); j++) {
+                    sb.append(" ");
+                }
+                System.out.println("sb.toString()="+sb.toString());
+                ans.add(sb.toString());
+            }else {
+                int totalSpace=maxWidth;
+                for (int j = 0; j < l.size(); j++) {
+                    totalSpace-=l.get(j).length();
+                }
+                int eachSpace=totalSpace/(l.size()-1);
+                int extraSpace=totalSpace-eachSpace*(l.size()-1);
+                StringBuffer sb=new StringBuffer();
+                for (int j = 0; j < l.size()-1; j++) {
+                    sb.append(l.get(j));
+                    for (int k = 0; k < eachSpace; k++) {
+                        sb.append(" ");
+                    }
+                    if (j<extraSpace) {
+                        sb.append(" ");
+                    }
+                }
+                sb.append(l.get(l.size()-1));
+                ans.add(sb.toString());
+            }
+        }
+        //处理最后一行
         List<String> l=sumList.get(sumList.size()-1);
         StringBuffer sb=new StringBuffer();
         for (int i = 0; i < l.size()-1; i++) {
-			sb.append(l.get(i));
-			sb.append(" ");
-		}
+            sb.append(l.get(i));
+            sb.append(" ");
+        }
         sb.append(l.get(l.size()-1));
         int tt=sb.toString().length();
         for (int j = 0; j < maxWidth-tt; j++) {
-			sb.append(" ");
-		}
+            sb.append(" ");
+        }
         ans.add(sb.toString());
-    	return ans;
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/069. Sqrt(x).java b/java/069. Sqrt(x).java
index ebc9f31..3232967 100644
--- a/java/069. Sqrt(x).java	
+++ b/java/069. Sqrt(x).java	
@@ -7,17 +7,17 @@ public int mySqrt(int x) {
             return 1;
         }
         int s=1;
-	for (int i = 0; i <20; i++) {
-		s=(x/s)/2+s/2;
-	}
-	int k=0;
-	int answer=0;
-	for (int i = -30; i < 30; i++) {
-		k=s+i;
-		if (k*k>0&&k*k<=x) {
-			answer=k;
-		}
-	}
-	return answer;
+    for (int i = 0; i <20; i++) {
+        s=(x/s)/2+s/2;
+    }
+    int k=0;
+    int answer=0;
+    for (int i = -30; i < 30; i++) {
+        k=s+i;
+        if (k*k>0&&k*k<=x) {
+            answer=k;
+        }
+    }
+    return answer;
     }
 }
\ No newline at end of file
diff --git a/java/070. Climbing Stairs.java b/java/070. Climbing Stairs.java
index 3911394..ee87759 100644
--- a/java/070. Climbing Stairs.java	
+++ b/java/070. Climbing Stairs.java	
@@ -1,15 +1,15 @@
 public class Solution {
     public int climbStairs(int n) {
         if (n<=2) {
-			return n;
-		}else {
-			int[] sk=new int[n];
-			sk[0]=1;
-			sk[1]=2;
-			for (int i =2; i < sk.length; i++) {
-				sk[i]=sk[i-1]+sk[i-2];
-			}
-			return sk[n-1];
-		}
+            return n;
+        }else {
+            int[] sk=new int[n];
+            sk[0]=1;
+            sk[1]=2;
+            for (int i =2; i < sk.length; i++) {
+                sk[i]=sk[i-1]+sk[i-2];
+            }
+            return sk[n-1];
+        }
     }
 }
\ No newline at end of file
diff --git a/java/072. Edit Distance.java b/java/072. Edit Distance.java
index e3a726c..d3f9fa7 100644
--- a/java/072. Edit Distance.java	
+++ b/java/072. Edit Distance.java	
@@ -3,26 +3,26 @@ public int minDistance(String word1, String word2) {
         int l1=word1.length();
         int l2=word2.length();
         if (l1*l2==0) {
-			return l1==0?l2:l1;
-		}
+            return l1==0?l2:l1;
+        }
         int[][] board=new int[l1+1][l2+1];
         for (int i = 0; i < l1+1; i++) {
-			board[i][0]=i;
-		}
+            board[i][0]=i;
+        }
         for (int i = 0; i < l2+1; i++) {
-			board[0][i]=i;
-		}
+            board[0][i]=i;
+        }
         char[] c1=word1.toCharArray();
         char[] c2=word2.toCharArray();
         for (int i = 1; i < l1+1; i++) {
-			for (int j = 1; j < l2+1; j++) {
-				if (c1[i-1]==c2[j-1]) {
-					board[i][j]=board[i-1][j-1];
-				}else {
-					board[i][j]=Math.min(Math.min(board[i-1][j], board[i][j-1]), board[i-1][j-1])+1;
-				}
-			}
-		}
+            for (int j = 1; j < l2+1; j++) {
+                if (c1[i-1]==c2[j-1]) {
+                    board[i][j]=board[i-1][j-1];
+                }else {
+                    board[i][j]=Math.min(Math.min(board[i-1][j], board[i][j-1]), board[i-1][j-1])+1;
+                }
+            }
+        }
         return board[l1][l2];
     }
 }
\ No newline at end of file
diff --git a/java/073. Set Matrix Zeroes.java b/java/073. Set Matrix Zeroes.java
index 369e501..ae50f07 100644
--- a/java/073. Set Matrix Zeroes.java	
+++ b/java/073. Set Matrix Zeroes.java	
@@ -1,42 +1,42 @@
 public class Solution {
     public void setZeroes(int[][] matrix) {
-    	boolean f=true;
-    	for (int i = 0; i < matrix.length; i++) {
-			if (matrix[i][0]==0) {
-				f=false;
-				break;
-			}
-		}
-    	boolean l=true;
-    	for (int i = 0; i < matrix[0].length; i++) {
-			if (matrix[0][i]==0) {
-				l=false;
-			}
-		}
+        boolean f=true;
         for (int i = 0; i < matrix.length; i++) {
-			for (int j = 0; j < matrix[i].length; j++) {
-				if (matrix[i][j]==0) {
-					matrix[i][0]=0;
-					matrix[0][j]=0;
-				}
-			}
-		}
+            if (matrix[i][0]==0) {
+                f=false;
+                break;
+            }
+        }
+        boolean l=true;
+        for (int i = 0; i < matrix[0].length; i++) {
+            if (matrix[0][i]==0) {
+                l=false;
+            }
+        }
+        for (int i = 0; i < matrix.length; i++) {
+            for (int j = 0; j < matrix[i].length; j++) {
+                if (matrix[i][j]==0) {
+                    matrix[i][0]=0;
+                    matrix[0][j]=0;
+                }
+            }
+        }
         for (int i = 1; i < matrix.length; i++) {
-			for (int j = 1; j < matrix[i].length; j++) {
-				if (matrix[i][0]==0||matrix[0][j]==0) {
-					matrix[i][j]=0;
-				}
-			}
-		}
+            for (int j = 1; j < matrix[i].length; j++) {
+                if (matrix[i][0]==0||matrix[0][j]==0) {
+                    matrix[i][j]=0;
+                }
+            }
+        }
         if (!f) {
-			for (int i = 0; i < matrix.length; i++) {
-				matrix[i][0]=0;
-			}
-		}
+            for (int i = 0; i < matrix.length; i++) {
+                matrix[i][0]=0;
+            }
+        }
         if (!l) {
-        	for (int i = 0; i < matrix[0].length; i++) {
-				matrix[0][i]=0;
-			}
-		}
+            for (int i = 0; i < matrix[0].length; i++) {
+                matrix[0][i]=0;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/074. Search a 2D Matrix.java b/java/074. Search a 2D Matrix.java
index 5f55259..a2d5a30 100644
--- a/java/074. Search a 2D Matrix.java	
+++ b/java/074. Search a 2D Matrix.java	
@@ -1,48 +1,48 @@
 public class Solution {
     public boolean searchMatrix(int[][] matrix, int target) {
-    	int begin=0;
-    	int end=matrix.length-1;
-    	int t=end/2;
-    	if (target<matrix[0][0]||target>matrix[matrix.length-1][matrix[matrix.length-1].length-1]) {
-			return false;
-		}
+        int begin=0;
+        int end=matrix.length-1;
+        int t=end/2;
+        if (target<matrix[0][0]||target>matrix[matrix.length-1][matrix[matrix.length-1].length-1]) {
+            return false;
+        }
         while (end-begin>1) {
-        	if (matrix[t][0]==target) {
-				return true;
-			}else if (matrix[end][0]<target) {
-				t=end;
-				begin=end;
-				break;
-			}else if (matrix[t][0]>target) {
-				end=t;
-				t=(begin+end)/2;
-			}else {
-				begin=t;
-				t=(begin+end)/2;
-			}
-		}
+            if (matrix[t][0]==target) {
+                return true;
+            }else if (matrix[end][0]<target) {
+                t=end;
+                begin=end;
+                break;
+            }else if (matrix[t][0]>target) {
+                end=t;
+                t=(begin+end)/2;
+            }else {
+                begin=t;
+                t=(begin+end)/2;
+            }
+        }
         if (matrix[t][0]==target||matrix[begin][0]==target||matrix[end][0]==target) {
-			return true;
-		}else if (matrix[t][0]>target) {
-			t=t-1;
-		}
+            return true;
+        }else if (matrix[t][0]>target) {
+            t=t-1;
+        }
         int b=0;
         int e=matrix[t].length-1;
         int tt=(b+e)/2;
         while (e-b>1) {
-        	if (matrix[t][tt]==target) {
-				return true;
-			}else if (matrix[t][tt]>target) {
-				e=tt;
-				tt=(b+e)/2;
-			}else {
-				b=tt;
-				tt=(b+e)/2;
-			}
-		}
+            if (matrix[t][tt]==target) {
+                return true;
+            }else if (matrix[t][tt]>target) {
+                e=tt;
+                tt=(b+e)/2;
+            }else {
+                b=tt;
+                tt=(b+e)/2;
+            }
+        }
         if (matrix[t][b]==target||matrix[t][e]==target) {
-			return true;
-		}
-    	return false;
+            return true;
+        }
+        return false;
     }
 }
\ No newline at end of file
diff --git a/java/075. Sort Colors.java b/java/075. Sort Colors.java
index 4db3dbe..7eeed81 100644
--- a/java/075. Sort Colors.java	
+++ b/java/075. Sort Colors.java	
@@ -1,47 +1,47 @@
 public class Solution {
     public void sortColors(int[] nums) {
-	int t=0;
-	int b=0;
-	int e=nums.length-1;
-	boolean flag=true;
+    int t=0;
+    int b=0;
+    int e=nums.length-1;
+    boolean flag=true;
     for (int i = 0; i < nums.length; i++) {
-			if (flag) {
-				if (nums[b]!=0) {
-					t=b;
-					flag=false;
-				}else {
-					t++;
-				}
-				b++;
-			}else {
-				if (nums[e]==0) {
-					nums[e]=nums[t];
-					nums[t]=0;
-					flag=true;
-					t++;
-				}
-				e--;
-			}
-	}
-	b=t;
-	e=nums.length-1;
-	flag=true;
-	 for (int i = t; i < nums.length; i++) {
-			if (flag) {
-				if (nums[b]!=1) {
-					t=b;
-					flag=false;
-				}
-				b++;
-			}else {
-				if (nums[e]==1) {
-					nums[e]=nums[t];
-					nums[t]=1;
-					flag=true;
-				}
-				e--;
-			}
-	}
+            if (flag) {
+                if (nums[b]!=0) {
+                    t=b;
+                    flag=false;
+                }else {
+                    t++;
+                }
+                b++;
+            }else {
+                if (nums[e]==0) {
+                    nums[e]=nums[t];
+                    nums[t]=0;
+                    flag=true;
+                    t++;
+                }
+                e--;
+            }
+    }
+    b=t;
+    e=nums.length-1;
+    flag=true;
+     for (int i = t; i < nums.length; i++) {
+            if (flag) {
+                if (nums[b]!=1) {
+                    t=b;
+                    flag=false;
+                }
+                b++;
+            }else {
+                if (nums[e]==1) {
+                    nums[e]=nums[t];
+                    nums[t]=1;
+                    flag=true;
+                }
+                e--;
+            }
+    }
     
         
     }
diff --git a/java/077. Combinations.java b/java/077. Combinations.java
index 870319d..55a6944 100644
--- a/java/077. Combinations.java	
+++ b/java/077. Combinations.java	
@@ -2,31 +2,31 @@ public class Solution {
     public List<List<Integer>> combine(int n, int k) {
         List<List<Integer>> answerList=new ArrayList<List<Integer>>();
         for (int i = 1; i <=n; i++) {
-			List<Integer> list=new ArrayList<Integer>();
-			list.add(i);
-			answerList.add(list);
-		}
+            List<Integer> list=new ArrayList<Integer>();
+            list.add(i);
+            answerList.add(list);
+        }
         for (int i = 0; i <answerList.size(); i++) {
-			if (answerList.get(i).size()<k) {
-				if ((n-answerList.get(i).get(answerList.get(i).size()-1))<(k-answerList.get(i).size())) {
-					answerList.remove(i);
-					i--;
-				}else {
-					for (int j = answerList.get(i).get(answerList.get(i).size()-1)+1; j <=n; j++) {
-						System.out.println("j="+j);
-						List<Integer> alist=new ArrayList<Integer>();
-						for (int l = 0; l <answerList.get(i).size(); l++) {
-							alist.add(answerList.get(i).get(l));
-						}
-						alist.add(j);
-                        answerList.add(alist);						
-					}
-					answerList.remove(i);
-					System.out.println();
-					i--;
-				}
-			}
-		}
-    	return answerList;
+            if (answerList.get(i).size()<k) {
+                if ((n-answerList.get(i).get(answerList.get(i).size()-1))<(k-answerList.get(i).size())) {
+                    answerList.remove(i);
+                    i--;
+                }else {
+                    for (int j = answerList.get(i).get(answerList.get(i).size()-1)+1; j <=n; j++) {
+                        System.out.println("j="+j);
+                        List<Integer> alist=new ArrayList<Integer>();
+                        for (int l = 0; l <answerList.get(i).size(); l++) {
+                            alist.add(answerList.get(i).get(l));
+                        }
+                        alist.add(j);
+                        answerList.add(alist);                        
+                    }
+                    answerList.remove(i);
+                    System.out.println();
+                    i--;
+                }
+            }
+        }
+        return answerList;
     }
 }
\ No newline at end of file
diff --git a/java/078. Subsets.java b/java/078. Subsets.java
index c5896ef..2cc45a5 100644
--- a/java/078. Subsets.java	
+++ b/java/078. Subsets.java	
@@ -1,30 +1,30 @@
 public class Solution {
     public List<List<Integer>> subsets(int[] nums) {
         for (int i = 0; i < nums.length; i++) {
-			for (int j = i+1; j < nums.length; j++) {
-				if (nums[i]>nums[j]) {
-					int temp=nums[i];
-					nums[i]=nums[j];
-					nums[j]=temp;
-				}
-			}
-		}
+            for (int j = i+1; j < nums.length; j++) {
+                if (nums[i]>nums[j]) {
+                    int temp=nums[i];
+                    nums[i]=nums[j];
+                    nums[j]=temp;
+                }
+            }
+        }
         int[] n=new int[nums.length];
         int sum=1;
         for (int i = 0; i < n.length; i++) {
-			n[i]=sum;
-			sum*=2;
-		}
+            n[i]=sum;
+            sum*=2;
+        }
         List<List<Integer>> answer=new ArrayList<List<Integer>>();
         for (int i = 0; i < sum; i++) {
-        	List<Integer> list=new ArrayList<Integer>();
-        	for (int j = 0; j < nums.length; j++) {
-				if ((i/n[j])%2==1) {
-					list.add(nums[j]);
-				}
-			}
-        	answer.add(list);
-		}
-    	return answer;
+            List<Integer> list=new ArrayList<Integer>();
+            for (int j = 0; j < nums.length; j++) {
+                if ((i/n[j])%2==1) {
+                    list.add(nums[j]);
+                }
+            }
+            answer.add(list);
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/079. Word Search.java b/java/079. Word Search.java
index 8c612a9..bfe479f 100644
--- a/java/079. Word Search.java	
+++ b/java/079. Word Search.java	
@@ -1,43 +1,43 @@
 public class Solution {
     public boolean exist(char[][] board, String word) {
-    	if (word==null||word.length()==0||board==null||board.length==0) {
-			return false;
-		}
-    	char[] ch=word.toCharArray();
-    	int length=ch.length;
-    	int m=board.length;
-    	int n=board[0].length;
-    	boolean[][] flag=new boolean[m][n];
-    	for (int i = 0; i < board.length; i++) {
-			for (int j = 0; j < board[i].length; j++) {
-				if (board[i][j]==ch[0]&&f(board,ch,0,i,j,length,m,n,flag)) {
-					return true;
-				}
-			}
-		}
+        if (word==null||word.length()==0||board==null||board.length==0) {
+            return false;
+        }
+        char[] ch=word.toCharArray();
+        int length=ch.length;
+        int m=board.length;
+        int n=board[0].length;
+        boolean[][] flag=new boolean[m][n];
+        for (int i = 0; i < board.length; i++) {
+            for (int j = 0; j < board[i].length; j++) {
+                if (board[i][j]==ch[0]&&f(board,ch,0,i,j,length,m,n,flag)) {
+                    return true;
+                }
+            }
+        }
         return false;
     }
     public boolean f(char[][] board,char[] ch,int level,int x,int y,int length,int m,int n,boolean[][] flag){
-    	if (level==length) {
-			return true;
-		}
-    	if (x<0||x>=m||y<0||y>=n||flag[x][y]||board[x][y]!=ch[level]) {
-			return false;
-		}
-    	flag[x][y]=true;
-    	if (f(board,ch,level+1,x+1,y,length,m,n,flag)) {
-			return true;
-		}
-    	if (f(board,ch,level+1,x-1,y,length,m,n,flag)) {
-			return true;
-		}
-    	if (f(board,ch,level+1,x,y+1,length,m,n,flag)) {
-			return true;
-		}
-    	if (f(board,ch,level+1,x,y-1,length,m,n,flag)) {
-			return true;
-		}
-    	flag[x][y]=false;
-    	return false;
+        if (level==length) {
+            return true;
+        }
+        if (x<0||x>=m||y<0||y>=n||flag[x][y]||board[x][y]!=ch[level]) {
+            return false;
+        }
+        flag[x][y]=true;
+        if (f(board,ch,level+1,x+1,y,length,m,n,flag)) {
+            return true;
+        }
+        if (f(board,ch,level+1,x-1,y,length,m,n,flag)) {
+            return true;
+        }
+        if (f(board,ch,level+1,x,y+1,length,m,n,flag)) {
+            return true;
+        }
+        if (f(board,ch,level+1,x,y-1,length,m,n,flag)) {
+            return true;
+        }
+        flag[x][y]=false;
+        return false;
     }
 }
\ No newline at end of file
diff --git a/java/080. Remove Duplicates from Sorted Array II.java b/java/080. Remove Duplicates from Sorted Array II.java
index 244f658..e733895 100644
--- a/java/080. Remove Duplicates from Sorted Array II.java	
+++ b/java/080. Remove Duplicates from Sorted Array II.java	
@@ -1,24 +1,24 @@
 public class Solution {
     public int removeDuplicates(int[] nums) {
-    	if (nums.length<3) {
-			return nums.length;
-		}
-    	boolean flag=true;
-    	int k=0;
-    	int t=nums[0];
+        if (nums.length<3) {
+            return nums.length;
+        }
+        boolean flag=true;
+        int k=0;
+        int t=nums[0];
         for (int i = 1; i < nums.length; i++) {
-        	t=nums[i-1];
-        	nums[i-k]=nums[i];
-        	if (nums[i]==t) {
-        		if (flag) {
-					flag=false;
-				}else {
-    				k++;
-				}
-        	}else {
-        		flag=true;
-			}
-		}
-    	return nums.length-k;
+            t=nums[i-1];
+            nums[i-k]=nums[i];
+            if (nums[i]==t) {
+                if (flag) {
+                    flag=false;
+                }else {
+                    k++;
+                }
+            }else {
+                flag=true;
+            }
+        }
+        return nums.length-k;
     }
 }
\ No newline at end of file
diff --git a/java/081. Search in Rotated Sorted Array II.java b/java/081. Search in Rotated Sorted Array II.java
index a6ba8fa..0d2a0a0 100644
--- a/java/081. Search in Rotated Sorted Array II.java	
+++ b/java/081. Search in Rotated Sorted Array II.java	
@@ -1,8 +1,8 @@
     public boolean search(int[] nums, int target) {
         for (int i = 0; i < nums.length; i++) {
-			if (nums[i]==target) {
-				return true;
-			}
-		}
+            if (nums[i]==target) {
+                return true;
+            }
+        }
         return false;
     }
diff --git a/java/082. Remove Duplicates from Sorted List II.java b/java/082. Remove Duplicates from Sorted List II.java
index cbd1003..5aa1535 100644
--- a/java/082. Remove Duplicates from Sorted List II.java	
+++ b/java/082. Remove Duplicates from Sorted List II.java	
@@ -8,23 +8,23 @@
  */
 public class Solution {
     public ListNode deleteDuplicates(ListNode head) {
-    	head=findFirst(head);
-    	if (head!=null) {
-			head.next=deleteDuplicates(head.next);
-		}
+        head=findFirst(head);
+        if (head!=null) {
+            head.next=deleteDuplicates(head.next);
+        }
         return head;
     }
     public ListNode findFirst(ListNode head) {
-    	if (head==null||head.next==null||head.val!=head.next.val) {
-    		return head;
-		}
-    	int i=head.val;
-    	while (head!=null) {
-			if (head.val!=i) {
-				return findFirst(head);
-			}
-			head=head.next;
-		}
-    	return null;
+        if (head==null||head.next==null||head.val!=head.next.val) {
+            return head;
+        }
+        int i=head.val;
+        while (head!=null) {
+            if (head.val!=i) {
+                return findFirst(head);
+            }
+            head=head.next;
+        }
+        return null;
     }
 }
\ No newline at end of file
diff --git a/java/083. Remove Duplicates from Sorted List.java b/java/083. Remove Duplicates from Sorted List.java
index 4776a6e..25ddda8 100644
--- a/java/083. Remove Duplicates from Sorted List.java	
+++ b/java/083. Remove Duplicates from Sorted List.java	
@@ -8,15 +8,15 @@
  */
 public class Solution {
     public ListNode deleteDuplicates(ListNode head) {
-    	if (head==null||head.next==null) {
-    		return head;
-		}
-    	if (head.val==head.next.val) {
-			head.next=head.next.next;
-			head=deleteDuplicates(head);
-		}else {
-			head.next=deleteDuplicates(head.next);
-		}
-    	return head;
+        if (head==null||head.next==null) {
+            return head;
+        }
+        if (head.val==head.next.val) {
+            head.next=head.next.next;
+            head=deleteDuplicates(head);
+        }else {
+            head.next=deleteDuplicates(head.next);
+        }
+        return head;
     }
 }
\ No newline at end of file
diff --git a/java/086. Partition List.java b/java/086. Partition List.java
index 785a8b1..ea42aef 100644
--- a/java/086. Partition List.java	
+++ b/java/086. Partition List.java	
@@ -8,39 +8,39 @@
  */
 public class Solution {
     public ListNode partition(ListNode head, int x) {
-    	List<ListNode> littleList=zuheL(head,new ArrayList<ListNode>(),x);
-    	List<ListNode> bigList=zuheB(head,new ArrayList<ListNode>(),x);
-    	int ll=littleList.size();
-    	int lb=bigList.size();
-    	if (ll==0||lb==0) {
-    		return head;
-		}
-    	for (int i = 0; i < ll-1; i++) {
-    		littleList.get(i).next=littleList.get(i+1);
-		}
-    	littleList.get(ll-1).next=bigList.get(0);
-    	for (int i = 0; i < lb-1; i++) {
-    		bigList.get(i).next=bigList.get(i+1);
-		}
-    	bigList.get(lb-1).next=null;
-    	return littleList.get(0);
+        List<ListNode> littleList=zuheL(head,new ArrayList<ListNode>(),x);
+        List<ListNode> bigList=zuheB(head,new ArrayList<ListNode>(),x);
+        int ll=littleList.size();
+        int lb=bigList.size();
+        if (ll==0||lb==0) {
+            return head;
+        }
+        for (int i = 0; i < ll-1; i++) {
+            littleList.get(i).next=littleList.get(i+1);
+        }
+        littleList.get(ll-1).next=bigList.get(0);
+        for (int i = 0; i < lb-1; i++) {
+            bigList.get(i).next=bigList.get(i+1);
+        }
+        bigList.get(lb-1).next=null;
+        return littleList.get(0);
     }
     public List<ListNode> zuheL(ListNode head,List<ListNode> list,int x){
-    	if (head!=null) {
-    		if (head.val<x) {
-    			list.add(head);
-			}
-			list=zuheL(head.next,list,x);
-		}
-    	return list;
+        if (head!=null) {
+            if (head.val<x) {
+                list.add(head);
+            }
+            list=zuheL(head.next,list,x);
+        }
+        return list;
     }
     public List<ListNode> zuheB(ListNode head,List<ListNode> list,int x){
-    	if (head!=null) {
-    		if (head.val>=x) {
-    			list.add(head);
-			}
-			list=zuheB(head.next,list,x);
-		}
-    	return list;
+        if (head!=null) {
+            if (head.val>=x) {
+                list.add(head);
+            }
+            list=zuheB(head.next,list,x);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/087. Scramble String.java b/java/087. Scramble String.java
index 14f8e08..2f9c64d 100644
--- a/java/087. Scramble String.java	
+++ b/java/087. Scramble String.java	
@@ -1,30 +1,30 @@
 public class Solution {
-	Map<String,Boolean> map=new HashMap<String, Boolean>();
+    Map<String,Boolean> map=new HashMap<String, Boolean>();
     public boolean isScramble(String s1, String s2) {
-    	if (map.get(s1+","+s2)!=null) {
-			return map.get(s1+","+s2);
-		}
-    	int length=s1.length();
-    	if (length!=s2.length()) {
-    	    map.put(s1+","+s2, false);
-			return false;
-		}
-    	boolean flag=false;
-    	if (length==1) {
-    	    flag=s1.equals(s2);
-    	    map.put(s1+","+s2, flag);
-    		return flag;
-		}
-    	for (int i = 1; i <length&&!flag; i++) {
-    		String s1b=s1.substring(0,i);
-    		String s1e=s1.substring(i,length);
-    		String s2b=s2.substring(0,i);
-    		String s2e=s2.substring(i,length);
-    		String ns2b=s2.substring(0,length-i);
-    		String ns2e=s2.substring(length-i,length);
-    		flag=(isScramble(s1b,s2b)&&isScramble(s1e,s2e))||(isScramble(s1b,ns2e)&&isScramble(s1e,ns2b));
-		}
-    	map.put(s1+","+s2, flag);
-    	return flag; 
+        if (map.get(s1+","+s2)!=null) {
+            return map.get(s1+","+s2);
+        }
+        int length=s1.length();
+        if (length!=s2.length()) {
+            map.put(s1+","+s2, false);
+            return false;
+        }
+        boolean flag=false;
+        if (length==1) {
+            flag=s1.equals(s2);
+            map.put(s1+","+s2, flag);
+            return flag;
+        }
+        for (int i = 1; i <length&&!flag; i++) {
+            String s1b=s1.substring(0,i);
+            String s1e=s1.substring(i,length);
+            String s2b=s2.substring(0,i);
+            String s2e=s2.substring(i,length);
+            String ns2b=s2.substring(0,length-i);
+            String ns2e=s2.substring(length-i,length);
+            flag=(isScramble(s1b,s2b)&&isScramble(s1e,s2e))||(isScramble(s1b,ns2e)&&isScramble(s1e,ns2b));
+        }
+        map.put(s1+","+s2, flag);
+        return flag; 
     }
 }
\ No newline at end of file
diff --git a/java/088. Merge Sorted Array.java b/java/088. Merge Sorted Array.java
index ea79717..e125102 100644
--- a/java/088. Merge Sorted Array.java	
+++ b/java/088. Merge Sorted Array.java	
@@ -1,22 +1,22 @@
 public class Solution {
     public void merge(int[] nums1, int m, int[] nums2, int n) {
         for (int i = m-1; i >=0; i--) {
-			nums1[i+nums1.length-m]=nums1[i];
-		}
+            nums1[i+nums1.length-m]=nums1[i];
+        }
         int a=nums1.length-m;
         int b=0;
         for (int i = 0; i < m+n; i++) {
-        	if (a==nums1.length) {
-        		nums1[i]=nums2[b];
-				b++;
-			}else if (b==n||nums1[a]<nums2[b]) {
-				nums1[i]=nums1[a];
-				a++;
-			}else {
-				nums1[i]=nums2[b];
-				b++;
-			}
-			
-		}
+            if (a==nums1.length) {
+                nums1[i]=nums2[b];
+                b++;
+            }else if (b==n||nums1[a]<nums2[b]) {
+                nums1[i]=nums1[a];
+                a++;
+            }else {
+                nums1[i]=nums2[b];
+                b++;
+            }
+            
+        }
     }
 }
\ No newline at end of file
diff --git a/java/089. Gray Code.java b/java/089. Gray Code.java
index 103361e..f059c47 100644
--- a/java/089. Gray Code.java	
+++ b/java/089. Gray Code.java	
@@ -1,26 +1,26 @@
 public class Solution {
     public List<Integer> grayCode(int n) {
-    	List<Integer> ans=new ArrayList<Integer>();
-    	List<String> list=new ArrayList<String>();
-    	if (n==0) {
-    	    ans.add(0);
-			return ans;
-		}
-    	list.add("0");
-    	list.add("1");
-    	for (int i = 1; i < n; i++) {
-    		List<String> newList=new ArrayList<String>();
-			for (int j = 0; j < list.size(); j++) {
-				newList.add("0"+list.get(j));
-			}
-			for (int j = list.size()-1; j >= 0 ; j--) {
-				newList.add("1"+list.get(j));
-			}
-			list=newList;
-		}
-    	for (int i = 0; i < list.size(); i++) {
-			ans.add(Integer.valueOf(list.get(i), 2));
-		}
-    	return ans;
+        List<Integer> ans=new ArrayList<Integer>();
+        List<String> list=new ArrayList<String>();
+        if (n==0) {
+            ans.add(0);
+            return ans;
+        }
+        list.add("0");
+        list.add("1");
+        for (int i = 1; i < n; i++) {
+            List<String> newList=new ArrayList<String>();
+            for (int j = 0; j < list.size(); j++) {
+                newList.add("0"+list.get(j));
+            }
+            for (int j = list.size()-1; j >= 0 ; j--) {
+                newList.add("1"+list.get(j));
+            }
+            list=newList;
+        }
+        for (int i = 0; i < list.size(); i++) {
+            ans.add(Integer.valueOf(list.get(i), 2));
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/090. Subsets II.java b/java/090. Subsets II.java
index 9972d7d..c42aea3 100644
--- a/java/090. Subsets II.java	
+++ b/java/090. Subsets II.java	
@@ -1,39 +1,39 @@
 public class Solution {
     public List<List<Integer>> subsetsWithDup(int[] nums) {
-    	for (int i = 0; i < nums.length; i++) {
-			for (int j = i+1; j < nums.length; j++) {
-				if (nums[i]<nums[j]) {
-					int temp=nums[i];
-					nums[i]=nums[j];
-					nums[j]=temp;
-				}
-			}
-		}
+        for (int i = 0; i < nums.length; i++) {
+            for (int j = i+1; j < nums.length; j++) {
+                if (nums[i]<nums[j]) {
+                    int temp=nums[i];
+                    nums[i]=nums[j];
+                    nums[j]=temp;
+                }
+            }
+        }
         int[] n=new int[nums.length];
         int sum=1;
         for (int i = n.length-1; i >=0;i--) {
-			n[i]=sum;
-			sum*=2;
-		}
+            n[i]=sum;
+            sum*=2;
+        }
         List<List<Integer>> answer=new ArrayList<List<Integer>>();
         for (int i = 0; i < sum; i++) {
-        	List<Integer> list=new ArrayList<Integer>();
-        	for (int j = nums.length-1; j >=0 ; j--) {
-				if ((i/n[j])%2==1) {
-					list.add(nums[j]);
-				}
-			}
-        	answer.add(list);
-		}
+            List<Integer> list=new ArrayList<Integer>();
+            for (int j = nums.length-1; j >=0 ; j--) {
+                if ((i/n[j])%2==1) {
+                    list.add(nums[j]);
+                }
+            }
+            answer.add(list);
+        }
         Map<List<Integer>, Integer> map=new HashMap<List<Integer>, Integer>();
         for (int i = 0; i < answer.size(); i++) {
-			if (map.get(answer.get(i))==null) {
-				map.put(answer.get(i), 1);
-			}else {
-				answer.remove(i);
-				i--;
-			}
-		}
-    	return answer;
+            if (map.get(answer.get(i))==null) {
+                map.put(answer.get(i), 1);
+            }else {
+                answer.remove(i);
+                i--;
+            }
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/091. Decode Ways.java b/java/091. Decode Ways.java
index edd9171..fbc086c 100644
--- a/java/091. Decode Ways.java	
+++ b/java/091. Decode Ways.java	
@@ -1,29 +1,29 @@
 public class Solution {
     public int numDecodings(String s) {
-    	if (s.length()==0) {
-			return 0;
-		}
+        if (s.length()==0) {
+            return 0;
+        }
         Map<String,Integer> map=new HashMap<String, Integer>();
         return f(s,map);
     }
     public int f(String s,Map<String,Integer> map){
-    	if (s.length()==0) {
-			return 1;
-		}
-    	if (map.get(s)==null) {
-    		int length=s.length();
-    		int one=-1;
-    		if (length>=1) {
-    			one=Integer.parseInt(s.substring(0,1));
-			}
-    		int two=-1;
-    		if (length>=2) {
-    			two=Integer.parseInt(s.substring(0,2));
-			}
-			int value=(one>0?f(s.substring(1,s.length()),map):0)+((one>0&&two>0&&two<27)?f(s.substring(2,s.length()),map):0);
-			map.put(s, value);
-			return value;
-		}
-    	return map.get(s);
+        if (s.length()==0) {
+            return 1;
+        }
+        if (map.get(s)==null) {
+            int length=s.length();
+            int one=-1;
+            if (length>=1) {
+                one=Integer.parseInt(s.substring(0,1));
+            }
+            int two=-1;
+            if (length>=2) {
+                two=Integer.parseInt(s.substring(0,2));
+            }
+            int value=(one>0?f(s.substring(1,s.length()),map):0)+((one>0&&two>0&&two<27)?f(s.substring(2,s.length()),map):0);
+            map.put(s, value);
+            return value;
+        }
+        return map.get(s);
     }
 }
\ No newline at end of file
diff --git a/java/092. Reverse Linked List II.java b/java/092. Reverse Linked List II.java
index d72ef24..6bc6dc7 100644
--- a/java/092. Reverse Linked List II.java	
+++ b/java/092. Reverse Linked List II.java	
@@ -8,23 +8,23 @@
  */
 public class Solution {
     public ListNode reverseBetween(ListNode head, int m, int n) {
-    	List<ListNode> list=f(head, new ArrayList<ListNode>());
-    	list.get(m-1).next=list.get(n-1).next;
-    	for (int i = n-1; i >=m; i--) {
-			list.get(i).next=list.get(i-1);
-		}
-    	if (m!=1) {
-			list.get(m-2).next=list.get(n-1);
-			return list.get(0);
-		}else {
-			return list.get(n-1);
-		}
+        List<ListNode> list=f(head, new ArrayList<ListNode>());
+        list.get(m-1).next=list.get(n-1).next;
+        for (int i = n-1; i >=m; i--) {
+            list.get(i).next=list.get(i-1);
+        }
+        if (m!=1) {
+            list.get(m-2).next=list.get(n-1);
+            return list.get(0);
+        }else {
+            return list.get(n-1);
+        }
     }
     public List<ListNode> f(ListNode head,List<ListNode> list){
-    	if (head!=null) {
-			list.add(head);
-			list=f(head.next,list);
-		}
-    	return list;
+        if (head!=null) {
+            list.add(head);
+            list=f(head.next,list);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/093. Restore IP Addresses.java b/java/093. Restore IP Addresses.java
index ab02e69..4e4efb9 100644
--- a/java/093. Restore IP Addresses.java	
+++ b/java/093. Restore IP Addresses.java	
@@ -1,32 +1,32 @@
 public class Solution {
     public List<String> restoreIpAddresses(String s) {
-    	List<String> answerList=new ArrayList<String>();
+        List<String> answerList=new ArrayList<String>();
         for (int i = 1; i <=3; i++) {
-			for (int j = 1; j <=3; j++) {
-				for (int k = 1; k <=3; k++) {
-					int[] a={i,j,k};
-					if (i+j+k<s.length()) {
-						String t=new Solution().validate(s, a);
-						if (!(t.equals(""))) {
-							answerList.add(t);
-						}
-					}
-				}
-			}
-		}
-    	return answerList;
+            for (int j = 1; j <=3; j++) {
+                for (int k = 1; k <=3; k++) {
+                    int[] a={i,j,k};
+                    if (i+j+k<s.length()) {
+                        String t=new Solution().validate(s, a);
+                        if (!(t.equals(""))) {
+                            answerList.add(t);
+                        }
+                    }
+                }
+            }
+        }
+        return answerList;
     }
     public String validate(String s,int[] a){
-    	String s4=s.substring(a[0]+a[1]+a[2],s.length());
-    	if (s4.length()>3||(s4.length()>1&&s4.substring(0, 1).equals("0"))||Integer.parseInt(s4)>255) {
-			return "";
-		}
-    	String s1=s.substring(0,a[0]);
-    	String s2=s.substring(a[0],a[0]+a[1]);
-    	String s3=s.substring(a[0]+a[1],a[0]+a[1]+a[2]);
-    	if ((s3.length()>1&&s3.substring(0, 1).equals("0"))||(s2.length()>1&&s2.substring(0, 1).equals("0"))||(s1.length()>1&&s1.substring(0, 1).equals("0"))||Integer.parseInt(s3)>255||Integer.parseInt(s2)>255||Integer.parseInt(s1)>255) {
-			return "";
-		}
-    	return s1+"."+s2+"."+s3+"."+s4;
+        String s4=s.substring(a[0]+a[1]+a[2],s.length());
+        if (s4.length()>3||(s4.length()>1&&s4.substring(0, 1).equals("0"))||Integer.parseInt(s4)>255) {
+            return "";
+        }
+        String s1=s.substring(0,a[0]);
+        String s2=s.substring(a[0],a[0]+a[1]);
+        String s3=s.substring(a[0]+a[1],a[0]+a[1]+a[2]);
+        if ((s3.length()>1&&s3.substring(0, 1).equals("0"))||(s2.length()>1&&s2.substring(0, 1).equals("0"))||(s1.length()>1&&s1.substring(0, 1).equals("0"))||Integer.parseInt(s3)>255||Integer.parseInt(s2)>255||Integer.parseInt(s1)>255) {
+            return "";
+        }
+        return s1+"."+s2+"."+s3+"."+s4;
     }
 }
\ No newline at end of file
diff --git a/java/094. Binary Tree Inorder Traversal.java b/java/094. Binary Tree Inorder Traversal.java
index 79b5ca9..a0aba43 100644
--- a/java/094. Binary Tree Inorder Traversal.java	
+++ b/java/094. Binary Tree Inorder Traversal.java	
@@ -9,14 +9,14 @@
  */
 public class Solution {
     public List<Integer> inorderTraversal(TreeNode root) {
-    	return inorder(root,new ArrayList<Integer>());
+        return inorder(root,new ArrayList<Integer>());
     }
     public List<Integer> inorder(TreeNode root,List<Integer> list){
-    	if (root!=null) {
-			list=inorder(root.left,list);
-		    list.add(root.val);
-			list=inorder(root.right,list);
-		}
-    	return list;
+        if (root!=null) {
+            list=inorder(root.left,list);
+            list.add(root.val);
+            list=inorder(root.right,list);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/095. Unique Binary Search Trees II.java b/java/095. Unique Binary Search Trees II.java
index ee50c4a..a862954 100644
--- a/java/095. Unique Binary Search Trees II.java	
+++ b/java/095. Unique Binary Search Trees II.java	
@@ -12,29 +12,29 @@ public List<TreeNode> generateTrees(int n) {
         return f(1,n,new HashMap<String, List<TreeNode>>());
     }
     public List<TreeNode> f(int s,int e,Map<String,List<TreeNode>> map) {
-    	if (map.get(""+s+","+e)==null) {
-    		List<TreeNode> ans=new ArrayList<TreeNode>();
-    		if (s>e) {
-				ans.add(null);
-			}else if (s==e) {
-				ans.add(new TreeNode(s));
-			}else {
-				for (int i = s; i <=e; i++) {
-					List<TreeNode> left=f(s,i-1,map);
-					List<TreeNode> right=f(i+1,e,map);
-					for (int j = 0; j < left.size(); j++) {
-						for (int k = 0; k < right.size(); k++) {
-							TreeNode node=new TreeNode(i);
-							node.left=left.get(j);
-							node.right=right.get(k);
-							ans.add(node);
-						}
-					}
-				}
-			}
-    		map.put(""+s+","+e, ans);
-			return ans;
-		}
-    	return map.get(""+s+","+e);
+        if (map.get(""+s+","+e)==null) {
+            List<TreeNode> ans=new ArrayList<TreeNode>();
+            if (s>e) {
+                ans.add(null);
+            }else if (s==e) {
+                ans.add(new TreeNode(s));
+            }else {
+                for (int i = s; i <=e; i++) {
+                    List<TreeNode> left=f(s,i-1,map);
+                    List<TreeNode> right=f(i+1,e,map);
+                    for (int j = 0; j < left.size(); j++) {
+                        for (int k = 0; k < right.size(); k++) {
+                            TreeNode node=new TreeNode(i);
+                            node.left=left.get(j);
+                            node.right=right.get(k);
+                            ans.add(node);
+                        }
+                    }
+                }
+            }
+            map.put(""+s+","+e, ans);
+            return ans;
+        }
+        return map.get(""+s+","+e);
     }
 }
\ No newline at end of file
diff --git a/java/096. Unique Binary Search Trees.java b/java/096. Unique Binary Search Trees.java
index b57aed6..843146a 100644
--- a/java/096. Unique Binary Search Trees.java	
+++ b/java/096. Unique Binary Search Trees.java	
@@ -1,24 +1,24 @@
 public class Solution {
     public int numTrees(int n) {
-    	return f(n,new HashMap<Integer, Integer>());
+        return f(n,new HashMap<Integer, Integer>());
     }
     public int f(int n,Map<Integer,Integer> map){
-    	if (map.get(n)!=null) {
-			return map.get(n);
-		}else {
-			
-			if (n==1||n==0) {
-				return 1;
-			}else {
-				int sum=0;
-				for (int i = 0; i < n; i++) {
-					int left=f(i,map);
-					int right=f((n-1-i),map);
-					sum+=(left*right);
-				}
-				map.put(n,sum);
-				return sum;
-			}
-		}
+        if (map.get(n)!=null) {
+            return map.get(n);
+        }else {
+            
+            if (n==1||n==0) {
+                return 1;
+            }else {
+                int sum=0;
+                for (int i = 0; i < n; i++) {
+                    int left=f(i,map);
+                    int right=f((n-1-i),map);
+                    sum+=(left*right);
+                }
+                map.put(n,sum);
+                return sum;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/097. Interleaving String.java b/java/097. Interleaving String.java
index 3f46ff0..9ed1345 100644
--- a/java/097. Interleaving String.java	
+++ b/java/097. Interleaving String.java	
@@ -1,52 +1,52 @@
 public class Solution {
     public boolean isInterleave(String s1, String s2, String s3) {
-    	return f(s1,s2,s3,new HashMap<String, Boolean>());
+        return f(s1,s2,s3,new HashMap<String, Boolean>());
     }
     public boolean f(String s1, String s2, String s3,Map<String,Boolean> map){
-    	if (map.get(s1+","+s2+","+s3)==null) {
-        	if (s3.length()!=(s1.length()+s2.length())) {
-        		return false;
-        	}
-        	if (s3.length()==0) {
-        		return true;
-        	}
-        	
-        	String w=s3.substring(0,1);
-        	boolean flag1=false;
-        	boolean flag2=false;
-        	if (s1.length()!=0) {
-        		if(s2.length()==0){
-        			flag1=s1.equals(s3);
-        		}else {
-        			String w1=s1.substring(0,1);
-        			if (w.equals(w1)) {
-        				flag1=f(s1.substring(1, s1.length()),s2,s3.substring(1, s3.length()),map);
-        			}
-    			}
-        		if (flag1) {
-        			return flag1;
-        		}else {
-        			map.put(s1.substring(1, s1.length())+","+s2+","+s3.substring(1, s3.length()),false);
-        		}
-        	}
-        	if (s2.length()!=0) {
-        		if (s1.length()==0) {
-        			flag2=s2.equals(s3);
-    			}else {
-    				String w2=s2.substring(0,1);
-    				if (w.equals(w2)) {
-    					flag2=f(s1,s2.substring(1, s2.length()),s3.substring(1, s3.length()),map);
-    				}
-    			}
-        		if (flag2) {
-        			return flag2;
-        		}else {
-        			map.put(s1+","+s2.substring(1, s2.length())+","+s3.substring(1, s3.length()),false);
-        			map.put(s1+","+s2+","+s3,false);
-        		}
-        	}
+        if (map.get(s1+","+s2+","+s3)==null) {
+            if (s3.length()!=(s1.length()+s2.length())) {
+                return false;
+            }
+            if (s3.length()==0) {
+                return true;
+            }
+            
+            String w=s3.substring(0,1);
+            boolean flag1=false;
+            boolean flag2=false;
+            if (s1.length()!=0) {
+                if(s2.length()==0){
+                    flag1=s1.equals(s3);
+                }else {
+                    String w1=s1.substring(0,1);
+                    if (w.equals(w1)) {
+                        flag1=f(s1.substring(1, s1.length()),s2,s3.substring(1, s3.length()),map);
+                    }
+                }
+                if (flag1) {
+                    return flag1;
+                }else {
+                    map.put(s1.substring(1, s1.length())+","+s2+","+s3.substring(1, s3.length()),false);
+                }
+            }
+            if (s2.length()!=0) {
+                if (s1.length()==0) {
+                    flag2=s2.equals(s3);
+                }else {
+                    String w2=s2.substring(0,1);
+                    if (w.equals(w2)) {
+                        flag2=f(s1,s2.substring(1, s2.length()),s3.substring(1, s3.length()),map);
+                    }
+                }
+                if (flag2) {
+                    return flag2;
+                }else {
+                    map.put(s1+","+s2.substring(1, s2.length())+","+s3.substring(1, s3.length()),false);
+                    map.put(s1+","+s2+","+s3,false);
+                }
+            }
         }
-    	return false;
+        return false;
     }
     
     
diff --git a/java/098. Validate Binary Search Tree.java b/java/098. Validate Binary Search Tree.java
index 7123633..f307ca5 100644
--- a/java/098. Validate Binary Search Tree.java	
+++ b/java/098. Validate Binary Search Tree.java	
@@ -9,19 +9,19 @@
  */
 public class Solution {
     public boolean isValidBST(TreeNode root) {
-    	if (root==null) {
-			return true;
-		}
-    	List<Integer> list=inorder(root,new ArrayList<Integer>());
-    	if (list.size()<2) {
-			return true;
-		}
-    	for (int i = 0; i < list.size()-1; i++) {
-			if (list.get(i)>=list.get(i+1)) {
-				return false;
-			}
-		}
-    	return true;
+        if (root==null) {
+            return true;
+        }
+        List<Integer> list=inorder(root,new ArrayList<Integer>());
+        if (list.size()<2) {
+            return true;
+        }
+        for (int i = 0; i < list.size()-1; i++) {
+            if (list.get(i)>=list.get(i+1)) {
+                return false;
+            }
+        }
+        return true;
     }
     public List<Integer> inorder(TreeNode root,List<Integer> list){  
         if (root!=null) {  
diff --git a/java/100. Same Tree.java b/java/100. Same Tree.java
index 99ff095..24d4b65 100644
--- a/java/100. Same Tree.java	
+++ b/java/100. Same Tree.java	
@@ -9,16 +9,16 @@
  */
 public class Solution {
     public boolean isSameTree(TreeNode p, TreeNode q) {
-    	if (p==null&&q==null) {
-			return true;
-		}else if (p==null||q==null) {
-			return false;
-		}
-    	if (p.val!=q.val) {
-			return false;
-		}else{
-			return isSameTree(p.left, q.left)&&isSameTree(p.right, q.right);
-		}
-		
+        if (p==null&&q==null) {
+            return true;
+        }else if (p==null||q==null) {
+            return false;
+        }
+        if (p.val!=q.val) {
+            return false;
+        }else{
+            return isSameTree(p.left, q.left)&&isSameTree(p.right, q.right);
+        }
+        
     }
 }
\ No newline at end of file
diff --git a/java/101. Symmetric Tree.java b/java/101. Symmetric Tree.java
index 480a62c..2417638 100644
--- a/java/101. Symmetric Tree.java	
+++ b/java/101. Symmetric Tree.java	
@@ -10,23 +10,23 @@
 public class Solution {
     public boolean isSymmetric(TreeNode root) {
         if (root==null) {
-			return true;
-		}else {
-			TreeNode p=root.left;
-			TreeNode q=root.right;
-			return isSy(p, q);
-		}
+            return true;
+        }else {
+            TreeNode p=root.left;
+            TreeNode q=root.right;
+            return isSy(p, q);
+        }
     }
     public boolean isSy(TreeNode p,TreeNode q){
-    	if (p==null&&q==null) {
-			return true;
-		}else if (p==null||q==null) {
-			return false;
-		}
-    	if (p.val!=q.val) {
-			return false;
-		}else{
-			return isSy(p.right, q.left)&&isSy(p.left, q.right);
-		}
+        if (p==null&&q==null) {
+            return true;
+        }else if (p==null||q==null) {
+            return false;
+        }
+        if (p.val!=q.val) {
+            return false;
+        }else{
+            return isSy(p.right, q.left)&&isSy(p.left, q.right);
+        }
     }
 }
\ No newline at end of file
diff --git a/java/102. Binary Tree Level Order Traversal.java b/java/102. Binary Tree Level Order Traversal.java
index d375e6c..bd5a4e3 100644
--- a/java/102. Binary Tree Level Order Traversal.java	
+++ b/java/102. Binary Tree Level Order Traversal.java	
@@ -9,32 +9,32 @@
  */
 public class Solution {
     public List<List<Integer>> levelOrder(TreeNode root) {
-		List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
-		List<List<Integer>> list = new ArrayList<List<Integer>>();
-		if (root == null) {
-			return list;
-		}
-		List<TreeNode> initList = new ArrayList<TreeNode>();
-		initList.add(root);
-		answerList.add(initList);
-		for (int i = 0; i < answerList.size(); i++) {
-			List<Integer> l = new ArrayList<Integer>();
-			List<TreeNode> newList = new ArrayList<TreeNode>();
-			for (int j = 0; j < answerList.get(i).size(); j++) {
-				TreeNode tree = answerList.get(i).get(j);
-				l.add(answerList.get(i).get(j).val);
-				if (tree.left != null) {
-					newList.add(tree.left);
-				}
-				if (tree.right != null) {
-					newList.add(tree.right);
-				}
-			}
-			list.add(l);
-			if (newList.size() != 0) {
-				answerList.add(newList);
-			}
-		}
-		return list;
-	}
+        List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
+        List<List<Integer>> list = new ArrayList<List<Integer>>();
+        if (root == null) {
+            return list;
+        }
+        List<TreeNode> initList = new ArrayList<TreeNode>();
+        initList.add(root);
+        answerList.add(initList);
+        for (int i = 0; i < answerList.size(); i++) {
+            List<Integer> l = new ArrayList<Integer>();
+            List<TreeNode> newList = new ArrayList<TreeNode>();
+            for (int j = 0; j < answerList.get(i).size(); j++) {
+                TreeNode tree = answerList.get(i).get(j);
+                l.add(answerList.get(i).get(j).val);
+                if (tree.left != null) {
+                    newList.add(tree.left);
+                }
+                if (tree.right != null) {
+                    newList.add(tree.right);
+                }
+            }
+            list.add(l);
+            if (newList.size() != 0) {
+                answerList.add(newList);
+            }
+        }
+        return list;
+    }
 }
\ No newline at end of file
diff --git a/java/103. Binary Tree Zigzag Level Order Traversal.java b/java/103. Binary Tree Zigzag Level Order Traversal.java
index ce26e94..34b4345 100644
--- a/java/103. Binary Tree Zigzag Level Order Traversal.java	
+++ b/java/103. Binary Tree Zigzag Level Order Traversal.java	
@@ -9,42 +9,42 @@
  */
 public class Solution {
     public List<List<Integer>> zigzagLevelOrder(TreeNode root) {
-		List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
-		List<List<Integer>> list = new ArrayList<List<Integer>>();
-		if (root == null) {
-			return list;
-		}
-		List<TreeNode> initList = new ArrayList<TreeNode>();
-		initList.add(root);
-		answerList.add(initList);
-		for (int i = 0; i < answerList.size(); i++) {
-			System.out.println("i=" + i);
-			List<Integer> l = new ArrayList<Integer>();
-			List<TreeNode> newList = new ArrayList<TreeNode>();
-			for (int j = answerList.get(i).size() - 1; j >= 0; j--) {
-				TreeNode tree = answerList.get(i).get(j);
-				l.add(answerList.get(i).get(j).val);
-				if (i % 2 == 1) {
-					if (tree.right != null) {
-						newList.add(tree.right);
-					}
-					if (tree.left != null) {
-						newList.add(tree.left);
-					}
-				} else {
-					if (tree.left != null) {
-						newList.add(tree.left);
-					}
-					if (tree.right != null) {
-						newList.add(tree.right);
-					}
-				}
-			}
-			list.add(l);
-			if (newList.size() != 0) {
-				answerList.add(newList);
-			}
-		}
-		return list;
-	}
+        List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
+        List<List<Integer>> list = new ArrayList<List<Integer>>();
+        if (root == null) {
+            return list;
+        }
+        List<TreeNode> initList = new ArrayList<TreeNode>();
+        initList.add(root);
+        answerList.add(initList);
+        for (int i = 0; i < answerList.size(); i++) {
+            System.out.println("i=" + i);
+            List<Integer> l = new ArrayList<Integer>();
+            List<TreeNode> newList = new ArrayList<TreeNode>();
+            for (int j = answerList.get(i).size() - 1; j >= 0; j--) {
+                TreeNode tree = answerList.get(i).get(j);
+                l.add(answerList.get(i).get(j).val);
+                if (i % 2 == 1) {
+                    if (tree.right != null) {
+                        newList.add(tree.right);
+                    }
+                    if (tree.left != null) {
+                        newList.add(tree.left);
+                    }
+                } else {
+                    if (tree.left != null) {
+                        newList.add(tree.left);
+                    }
+                    if (tree.right != null) {
+                        newList.add(tree.right);
+                    }
+                }
+            }
+            list.add(l);
+            if (newList.size() != 0) {
+                answerList.add(newList);
+            }
+        }
+        return list;
+    }
 }
\ No newline at end of file
diff --git a/java/104. Maximum Depth of Binary Tree.java b/java/104. Maximum Depth of Binary Tree.java
index 5910891..0510054 100644
--- a/java/104. Maximum Depth of Binary Tree.java	
+++ b/java/104. Maximum Depth of Binary Tree.java	
@@ -9,28 +9,28 @@
  */
 public class Solution {
     public int maxDepth(TreeNode root) {
-		if (root==null) {
-			return 0;
-		}
-		if(root.left==null&&root.right==null){
-		    return 1;
-		}
-		int left=-1;
-		if(root.left!=null){
-		   left=maxDepth(root.left)+1;
-		}
-		int right=-1;
-		if(root.right!=null){
-		   right=maxDepth(root.right)+1;
-		}
-		if(left==-1){
-		    return right;
-		}
-		if(right==-1){
-		    return left;
-		}
-	
-		
-		return Math.max(left, right);
-	}
+        if (root==null) {
+            return 0;
+        }
+        if(root.left==null&&root.right==null){
+            return 1;
+        }
+        int left=-1;
+        if(root.left!=null){
+           left=maxDepth(root.left)+1;
+        }
+        int right=-1;
+        if(root.right!=null){
+           right=maxDepth(root.right)+1;
+        }
+        if(left==-1){
+            return right;
+        }
+        if(right==-1){
+            return left;
+        }
+    
+        
+        return Math.max(left, right);
+    }
 }
\ No newline at end of file
diff --git a/java/105. Construct Binary Tree from Preorder and Inorder Traversal.java b/java/105. Construct Binary Tree from Preorder and Inorder Traversal.java
index 609cde8..3ce4f9d 100644
--- a/java/105. Construct Binary Tree from Preorder and Inorder Traversal.java	
+++ b/java/105. Construct Binary Tree from Preorder and Inorder Traversal.java	
@@ -9,24 +9,24 @@
  */
 public class Solution {
     public TreeNode buildTree(int[] preorder, int[] inorder) {
-    	return build(preorder, inorder,0,preorder.length-1,0,inorder.length-1);
+        return build(preorder, inorder,0,preorder.length-1,0,inorder.length-1);
     }
     public TreeNode build(int[] preorder, int[] inorder,int ps,int pe,int is,int ie){
-    	if(ps>pe){
-    		return null;
-    	}
-    	int val=preorder[ps];
-    	TreeNode node=new TreeNode(val);
-    	int i = is;
-    	for (; i <=ie; i++) {
-			if (inorder[i]==val) {
-				break;
-			}
-		}
-    	int rang=i-is;
-    	node.left=build(preorder, inorder,ps+1,ps+rang,is,i-1);
-    	node.right=build(preorder,inorder,ps+rang+1,pe,i+1,ie);
-    	return node;
-    	
+        if(ps>pe){
+            return null;
+        }
+        int val=preorder[ps];
+        TreeNode node=new TreeNode(val);
+        int i = is;
+        for (; i <=ie; i++) {
+            if (inorder[i]==val) {
+                break;
+            }
+        }
+        int rang=i-is;
+        node.left=build(preorder, inorder,ps+1,ps+rang,is,i-1);
+        node.right=build(preorder,inorder,ps+rang+1,pe,i+1,ie);
+        return node;
+        
     }
 }
\ No newline at end of file
diff --git a/java/106. Construct Binary Tree from Inorder and Postorder Traversal.java b/java/106. Construct Binary Tree from Inorder and Postorder Traversal.java
index 357ea0e..e2924d9 100644
--- a/java/106. Construct Binary Tree from Inorder and Postorder Traversal.java	
+++ b/java/106. Construct Binary Tree from Inorder and Postorder Traversal.java	
@@ -9,24 +9,24 @@
  */
 public class Solution {
     public TreeNode buildTree(int[] inorder, int[] postorder) {
-    	return build(inorder, postorder,0,inorder.length-1,0,postorder.length-1);
+        return build(inorder, postorder,0,inorder.length-1,0,postorder.length-1);
     }
     public TreeNode build(int[] inorder, int[] postorder,int is,int ie,int ps,int pe){
-    	if(ps>pe){
-    		return null;
-    	}
-    	int val=postorder[pe];
-    	TreeNode node=new TreeNode(val);
-    	int i = is;
-    	for (; i <=ie; i++) {
-			if (inorder[i]==val) {
-				break;
-			}
-		}
-    	int rang=i-is;
-    	node.left=build(inorder, postorder,is,i-1,ps,ps+rang-1);
-    	node.right=build(inorder,postorder,i+1,ie,ps+rang,pe-1);
-    	return node;
-    	
+        if(ps>pe){
+            return null;
+        }
+        int val=postorder[pe];
+        TreeNode node=new TreeNode(val);
+        int i = is;
+        for (; i <=ie; i++) {
+            if (inorder[i]==val) {
+                break;
+            }
+        }
+        int rang=i-is;
+        node.left=build(inorder, postorder,is,i-1,ps,ps+rang-1);
+        node.right=build(inorder,postorder,i+1,ie,ps+rang,pe-1);
+        return node;
+        
     }
 }
\ No newline at end of file
diff --git a/java/107. Binary Tree Level Order Traversal II.java b/java/107. Binary Tree Level Order Traversal II.java
index 4fdd182..0e11503 100644
--- a/java/107. Binary Tree Level Order Traversal II.java	
+++ b/java/107. Binary Tree Level Order Traversal II.java	
@@ -9,37 +9,37 @@
  */
 public class Solution {
     public List<List<Integer>> levelOrderBottom(TreeNode root) {
-		List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
-		List<List<Integer>> list = new ArrayList<List<Integer>>();
-		if (root == null) {
-			return list;
-		}
-		List<TreeNode> initList = new ArrayList<TreeNode>();
-		initList.add(root);
-		answerList.add(initList);
-		for (int i = 0; i < answerList.size(); i++) {
-			List<TreeNode> newList = new ArrayList<TreeNode>();
-			for (int j = 0; j < answerList.get(i).size(); j++) {
-				TreeNode tree = answerList.get(i).get(j);
-				if (tree.left != null) {
-					newList.add(tree.left);
-				}
-				if (tree.right != null) {
-					newList.add(tree.right);
-				}
-			}
-			if (newList.size() != 0) {
-				answerList.add(newList);
-			}
-		}
-		for (int i = answerList.size()-1; i >=0; i--) {
-			List<Integer> l = new ArrayList<Integer>();
-			for (int j = 0; j < answerList.get(i).size(); j++) {
-				l.add(answerList.get(i).get(j).val);
-			}
-			list.add(l);
-		}
-		
-		return list;
-	}
+        List<List<TreeNode>> answerList = new ArrayList<List<TreeNode>>();
+        List<List<Integer>> list = new ArrayList<List<Integer>>();
+        if (root == null) {
+            return list;
+        }
+        List<TreeNode> initList = new ArrayList<TreeNode>();
+        initList.add(root);
+        answerList.add(initList);
+        for (int i = 0; i < answerList.size(); i++) {
+            List<TreeNode> newList = new ArrayList<TreeNode>();
+            for (int j = 0; j < answerList.get(i).size(); j++) {
+                TreeNode tree = answerList.get(i).get(j);
+                if (tree.left != null) {
+                    newList.add(tree.left);
+                }
+                if (tree.right != null) {
+                    newList.add(tree.right);
+                }
+            }
+            if (newList.size() != 0) {
+                answerList.add(newList);
+            }
+        }
+        for (int i = answerList.size()-1; i >=0; i--) {
+            List<Integer> l = new ArrayList<Integer>();
+            for (int j = 0; j < answerList.get(i).size(); j++) {
+                l.add(answerList.get(i).get(j).val);
+            }
+            list.add(l);
+        }
+        
+        return list;
+    }
 }
\ No newline at end of file
diff --git a/java/108. Convert Sorted Array to Binary Search Tree.java b/java/108. Convert Sorted Array to Binary Search Tree.java
index 8ae5e5a..3c3eb3c 100644
--- a/java/108. Convert Sorted Array to Binary Search Tree.java	
+++ b/java/108. Convert Sorted Array to Binary Search Tree.java	
@@ -9,17 +9,17 @@
  */
 public class Solution {
     public TreeNode sortedArrayToBST(int[] nums) {
-    	return build(nums,0,nums.length-1);
+        return build(nums,0,nums.length-1);
     }
     public TreeNode build(int[] nums,int s,int e){
-    	if (s>e) {
-			return null;
-		}
-    	int m=(s+e)/2;
+        if (s>e) {
+            return null;
+        }
+        int m=(s+e)/2;
         int val=nums[m];
         TreeNode node=new TreeNode(val);
         node.left=build(nums,s,m-1);
-		node.right=build(nums,m+1,e);
-    	return node;
+        node.right=build(nums,m+1,e);
+        return node;
     }
 }
\ No newline at end of file
diff --git a/java/109. Convert Sorted List to Binary Search Tree.java b/java/109. Convert Sorted List to Binary Search Tree.java
index 95504ef..5807186 100644
--- a/java/109. Convert Sorted List to Binary Search Tree.java	
+++ b/java/109. Convert Sorted List to Binary Search Tree.java	
@@ -17,21 +17,21 @@
  */
 public class Solution {
     public TreeNode sortedListToBST(ListNode head) {
-    	return f(head,null);
+        return f(head,null);
     }
     public TreeNode f(ListNode head,ListNode end) {
-    	if (head==end) {
-			return null;
-		}
+        if (head==end) {
+            return null;
+        }
         ListNode fast=head;
         ListNode slow=head;
-    	while (fast.next!=end&&fast.next.next!=end) {
-			fast=fast.next.next;
-			slow=slow.next;
-		}
-    	TreeNode node=new TreeNode(slow.val);
-    	node.right=f(slow.next,end);
-    	node.left=f(head,slow);
-    	return node;
+        while (fast.next!=end&&fast.next.next!=end) {
+            fast=fast.next.next;
+            slow=slow.next;
+        }
+        TreeNode node=new TreeNode(slow.val);
+        node.right=f(slow.next,end);
+        node.left=f(head,slow);
+        return node;
     }
 }
\ No newline at end of file
diff --git a/java/110. Balanced Binary Tree.java b/java/110. Balanced Binary Tree.java
index 6aefe3a..37852ca 100644
--- a/java/110. Balanced Binary Tree.java	
+++ b/java/110. Balanced Binary Tree.java	
@@ -10,18 +10,18 @@
 public class Solution {
     public boolean isBalanced(TreeNode root) {
         if (root==null) {
-			return true;
-		}
+            return true;
+        }
         if (Math.abs(f(root.left)-f(root.right))>1) {
-			return false;
-		}
+            return false;
+        }
         return isBalanced(root.left)&&isBalanced(root.right);
     }
     public int f(TreeNode root){
-    	if (root==null) {
-			return 0;
-		}else {
-			return 1+Math.max(f(root.left), f(root.right));
-		}
+        if (root==null) {
+            return 0;
+        }else {
+            return 1+Math.max(f(root.left), f(root.right));
+        }
     }
 }
\ No newline at end of file
diff --git a/java/111. Minimum Depth of Binary Tree.java b/java/111. Minimum Depth of Binary Tree.java
index 0c3654f..9177ffc 100644
--- a/java/111. Minimum Depth of Binary Tree.java	
+++ b/java/111. Minimum Depth of Binary Tree.java	
@@ -8,29 +8,29 @@
  * }
  */
 public class Solution {
-	public int minDepth(TreeNode root) {
-		if (root==null) {
-			return 0;
-		}
-		if(root.left==null&&root.right==null){
-		    return 1;
-		}
-		int left=-1;
-		if(root.left!=null){
-		   left=minDepth(root.left)+1;
-		}
-		int right=-1;
-		if(root.right!=null){
-		   right=minDepth(root.right)+1;
-		}
-		if(left==-1){
-		    return right;
-		}
-		if(right==-1){
-		    return left;
-		}
-	
-		
-		return Math.min(left, right);
-	}
+    public int minDepth(TreeNode root) {
+        if (root==null) {
+            return 0;
+        }
+        if(root.left==null&&root.right==null){
+            return 1;
+        }
+        int left=-1;
+        if(root.left!=null){
+           left=minDepth(root.left)+1;
+        }
+        int right=-1;
+        if(root.right!=null){
+           right=minDepth(root.right)+1;
+        }
+        if(left==-1){
+            return right;
+        }
+        if(right==-1){
+            return left;
+        }
+    
+        
+        return Math.min(left, right);
+    }
 }
\ No newline at end of file
diff --git a/java/112. Path Sum.java b/java/112. Path Sum.java
index edce037..249f4ed 100644
--- a/java/112. Path Sum.java	
+++ b/java/112. Path Sum.java	
@@ -9,22 +9,22 @@
  */
 public class Solution {
     public boolean hasPathSum(TreeNode root, int sum) {
-    	if (root==null) {
-    		return false;
-		}
-    	boolean flag1=false;
-    	if (root.val==sum&&root.left==null&&root.right==null) {
-			return true;
-		}
-    	if (root.left!=null) {
-			flag1=hasPathSum(root.left, sum-root.val);
-		}
-    	if (flag1) {
-			return true;
-		}
-    	if (root.right!=null) {
-    		return hasPathSum(root.right, sum-root.val);
-		}
-    	return false;
+        if (root==null) {
+            return false;
+        }
+        boolean flag1=false;
+        if (root.val==sum&&root.left==null&&root.right==null) {
+            return true;
+        }
+        if (root.left!=null) {
+            flag1=hasPathSum(root.left, sum-root.val);
+        }
+        if (flag1) {
+            return true;
+        }
+        if (root.right!=null) {
+            return hasPathSum(root.right, sum-root.val);
+        }
+        return false;
     }
 }
\ No newline at end of file
diff --git a/java/113. Path Sum II.java b/java/113. Path Sum II.java
index 7a813b6..4959734 100644
--- a/java/113. Path Sum II.java	
+++ b/java/113. Path Sum II.java	
@@ -9,46 +9,46 @@
  */
 public class Solution {
     public List<List<Integer>> pathSum(TreeNode root, int sum) {
-    	List<List<Integer>> answerList=new ArrayList<List<Integer>>();
-    	if (root==null) {
-			return answerList;
-		}
-    	List<List<TreeNode>> rootList=new ArrayList<List<TreeNode>>();
-    	List<TreeNode> initList=new ArrayList<TreeNode>();
-    	initList.add(root);
-    	rootList.add(initList);
+        List<List<Integer>> answerList=new ArrayList<List<Integer>>();
+        if (root==null) {
+            return answerList;
+        }
+        List<List<TreeNode>> rootList=new ArrayList<List<TreeNode>>();
+        List<TreeNode> initList=new ArrayList<TreeNode>();
+        initList.add(root);
+        rootList.add(initList);
         for (int i = 0; i < rootList.size(); i++) {
-        	List<TreeNode> list=rootList.get(i);
-        	TreeNode node=list.get(list.size()-1);
-        	if (node.left!=null||node.right!=null) {
-				if (node.left!=null) {
-					List<TreeNode> newLeftList=new ArrayList<TreeNode>();
-					newLeftList.addAll(list);
-					newLeftList.add(node.left);
-					rootList.add(newLeftList);
-				}
-				if (node.right!=null) {
-					List<TreeNode> newRightList=new ArrayList<TreeNode>();
-					newRightList.addAll(list);
-					newRightList.add(node.right);
-					rootList.add(newRightList);
-				}
-				rootList.remove(i);
-				i--;
-			}
-		}
+            List<TreeNode> list=rootList.get(i);
+            TreeNode node=list.get(list.size()-1);
+            if (node.left!=null||node.right!=null) {
+                if (node.left!=null) {
+                    List<TreeNode> newLeftList=new ArrayList<TreeNode>();
+                    newLeftList.addAll(list);
+                    newLeftList.add(node.left);
+                    rootList.add(newLeftList);
+                }
+                if (node.right!=null) {
+                    List<TreeNode> newRightList=new ArrayList<TreeNode>();
+                    newRightList.addAll(list);
+                    newRightList.add(node.right);
+                    rootList.add(newRightList);
+                }
+                rootList.remove(i);
+                i--;
+            }
+        }
         for (int i = 0; i < rootList.size(); i++) {
-        	List<TreeNode> list=rootList.get(i);
-        	List<Integer> valList=new ArrayList<Integer>();
-        	int val=0;
-        	for (int j = 0; j < list.size(); j++) {
-				val+=list.get(j).val;
-				valList.add(list.get(j).val);
-			}
-        	if (val==sum) {
-				answerList.add(valList);
-			}
-		}
-    	return answerList;
+            List<TreeNode> list=rootList.get(i);
+            List<Integer> valList=new ArrayList<Integer>();
+            int val=0;
+            for (int j = 0; j < list.size(); j++) {
+                val+=list.get(j).val;
+                valList.add(list.get(j).val);
+            }
+            if (val==sum) {
+                answerList.add(valList);
+            }
+        }
+        return answerList;
     }
 }
\ No newline at end of file
diff --git a/java/114. Flatten Binary Tree to Linked List.java b/java/114. Flatten Binary Tree to Linked List.java
index 3ff58ea..a50a440 100644
--- a/java/114. Flatten Binary Tree to Linked List.java	
+++ b/java/114. Flatten Binary Tree to Linked List.java	
@@ -8,22 +8,22 @@
  * }
  */
 public class Solution {
-	List<TreeNode> list=new ArrayList<TreeNode>();
+    List<TreeNode> list=new ArrayList<TreeNode>();
     public void flatten(TreeNode root) {
         if (root!=null) {
-        	f(root);
-        	for (int i = 0; i < list.size()-1; i++) {
-				list.get(i).right=list.get(i+1);
-				list.get(i).left=null;
-			}
+            f(root);
+            for (int i = 0; i < list.size()-1; i++) {
+                list.get(i).right=list.get(i+1);
+                list.get(i).left=null;
+            }
             root=list.get(0);
-		}
+        }
     }
     public void f(TreeNode root){
-    	if (root!=null) {
-			list.add(root);
-			f(root.left);
-			f(root.right);
-		}
+        if (root!=null) {
+            list.add(root);
+            f(root.left);
+            f(root.right);
+        }
     }
 }
\ No newline at end of file
diff --git a/java/116. Populating Next Right Pointers in Each Node.java b/java/116. Populating Next Right Pointers in Each Node.java
index a0cb7af..5cb211e 100644
--- a/java/116. Populating Next Right Pointers in Each Node.java	
+++ b/java/116. Populating Next Right Pointers in Each Node.java	
@@ -8,34 +8,34 @@
  */
 public class Solution {
     public void connect(TreeLinkNode root) {
-    	if (root!=null) {
-			List<List<TreeLinkNode>> sumList=new ArrayList<List<TreeLinkNode>>();
-			List<TreeLinkNode> initList=new ArrayList<TreeLinkNode>();
-			initList.add(root);
-			sumList.add(initList);
-			for (int i = 0; i < sumList.size(); i++) {
-				List<TreeLinkNode> list=sumList.get(i);
-				List<TreeLinkNode> newList=new ArrayList<TreeLinkNode>();
-				for (int j = 0; j < list.size(); j++) {
-					if (list.get(i).left!=null) {
-						newList.add(list.get(j).left);
-						newList.add(list.get(j).right);
-					}
-				}
-				if (newList.size()!=0) {
-					sumList.add(newList);
-				}
-			}
-			for (int i = 0; i < sumList.size(); i++) {
-				List<TreeLinkNode> list=sumList.get(i);
-				for (int j = 0; j < list.size(); j++) {
-					if (j<list.size()-1) {
-						list.get(j).next=list.get(j+1);
-					}else {
-						list.get(j).next=null;
-					}
-				}
-			}
-		}
+        if (root!=null) {
+            List<List<TreeLinkNode>> sumList=new ArrayList<List<TreeLinkNode>>();
+            List<TreeLinkNode> initList=new ArrayList<TreeLinkNode>();
+            initList.add(root);
+            sumList.add(initList);
+            for (int i = 0; i < sumList.size(); i++) {
+                List<TreeLinkNode> list=sumList.get(i);
+                List<TreeLinkNode> newList=new ArrayList<TreeLinkNode>();
+                for (int j = 0; j < list.size(); j++) {
+                    if (list.get(i).left!=null) {
+                        newList.add(list.get(j).left);
+                        newList.add(list.get(j).right);
+                    }
+                }
+                if (newList.size()!=0) {
+                    sumList.add(newList);
+                }
+            }
+            for (int i = 0; i < sumList.size(); i++) {
+                List<TreeLinkNode> list=sumList.get(i);
+                for (int j = 0; j < list.size(); j++) {
+                    if (j<list.size()-1) {
+                        list.get(j).next=list.get(j+1);
+                    }else {
+                        list.get(j).next=null;
+                    }
+                }
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/117. Populating Next Right Pointers in Each Node II.java b/java/117. Populating Next Right Pointers in Each Node II.java
index ca339c8..97c49a0 100644
--- a/java/117. Populating Next Right Pointers in Each Node II.java	
+++ b/java/117. Populating Next Right Pointers in Each Node II.java	
@@ -9,28 +9,28 @@
 public class Solution {
     public void connect(TreeLinkNode root) {
         if (root!=null) {
-        	TreeLinkNode rootNext=root.next;
-        	TreeLinkNode sonNext=null;
-        	while (rootNext!=null&&sonNext==null) {
-				if (rootNext.left!=null) {
-					sonNext=rootNext.left;
-				}else {
-					sonNext=rootNext.right;
-				}
-				rootNext=rootNext.next;
-			}
-        	if (root.left!=null) {
-				if (root.right!=null) {
-					root.left.next=root.right;
-				}else {
-					root.left.next=sonNext;
-				}
-			}
-        	if (root.right!=null) {
-				root.right.next=sonNext;
-			}
-        	connect(root.right);
-        	connect(root.left);
-		}
+            TreeLinkNode rootNext=root.next;
+            TreeLinkNode sonNext=null;
+            while (rootNext!=null&&sonNext==null) {
+                if (rootNext.left!=null) {
+                    sonNext=rootNext.left;
+                }else {
+                    sonNext=rootNext.right;
+                }
+                rootNext=rootNext.next;
+            }
+            if (root.left!=null) {
+                if (root.right!=null) {
+                    root.left.next=root.right;
+                }else {
+                    root.left.next=sonNext;
+                }
+            }
+            if (root.right!=null) {
+                root.right.next=sonNext;
+            }
+            connect(root.right);
+            connect(root.left);
+        }
     }
 }
\ No newline at end of file
diff --git a/java/118. Pascal's Triangle.java b/java/118. Pascal's Triangle.java
index 5220351..16f4ce4 100644
--- a/java/118. Pascal's Triangle.java	
+++ b/java/118. Pascal's Triangle.java	
@@ -1,18 +1,18 @@
 public class Solution {
     public List<List<Integer>> generate(int numRows) {
-		List<List<Integer>> answerList = new ArrayList<List<Integer>>();
-		for (int i = 0; i < numRows; i++) {
-			List<Integer> list = new ArrayList<Integer>();
-			for (int j = 0; j <= i; j++) {
-				if (j==0||j==i) {
-					list.add(1);
-				}else {
-					list.add(answerList.get(i-1).get(j-1)+answerList.get(i-1).get(j));
-				}
-			}
-			answerList.add(list);
-		}
+        List<List<Integer>> answerList = new ArrayList<List<Integer>>();
+        for (int i = 0; i < numRows; i++) {
+            List<Integer> list = new ArrayList<Integer>();
+            for (int j = 0; j <= i; j++) {
+                if (j==0||j==i) {
+                    list.add(1);
+                }else {
+                    list.add(answerList.get(i-1).get(j-1)+answerList.get(i-1).get(j));
+                }
+            }
+            answerList.add(list);
+        }
 
-		return answerList;
-	}
+        return answerList;
+    }
 }
\ No newline at end of file
diff --git a/java/119. Pascal's Triangle II.java b/java/119. Pascal's Triangle II.java
index f8c3654..5504f01 100644
--- a/java/119. Pascal's Triangle II.java	
+++ b/java/119. Pascal's Triangle II.java	
@@ -1,17 +1,17 @@
 public class Solution {
     public List<Integer> getRow(int rowIndex) {
-    	Map<Integer, Integer> map=new HashMap<Integer, Integer>();
+        Map<Integer, Integer> map=new HashMap<Integer, Integer>();
         for (int i = 0; i <=rowIndex; i++) {
-			map.put(i, 1);
-			//反向计算防止值在使用前被覆盖
-			for (int j = i-1; j >=1; j--) {
-				map.put(j, map.get(j-1)+map.get(j));
-			}
-		}
+            map.put(i, 1);
+            //反向计算防止值在使用前被覆盖
+            for (int j = i-1; j >=1; j--) {
+                map.put(j, map.get(j-1)+map.get(j));
+            }
+        }
         List<Integer> answerList=new ArrayList<Integer>();
-    	for (int i = 0; i <=rowIndex; i++) {
-			answerList.add(map.get(i));
-		}
-    	return answerList;
+        for (int i = 0; i <=rowIndex; i++) {
+            answerList.add(map.get(i));
+        }
+        return answerList;
     }
 }
\ No newline at end of file
diff --git a/java/120. Triangle.java b/java/120. Triangle.java
index 40df1f1..48ec636 100644
--- a/java/120. Triangle.java	
+++ b/java/120. Triangle.java	
@@ -1,17 +1,17 @@
 public class Solution {
     public int minimumTotal(List<List<Integer>> triangle) {
-    	int[] ans=new int[triangle.get(triangle.size()-1).size()];
-    	for (int i = 0; i <triangle.get(triangle.size()-1).size(); i++) {
-			ans[i]=triangle.get(triangle.size()-1).get(i);
-		}
-    	if (triangle.size()>1) {
-    		for (int i = triangle.size()-2; i >=0; i--) {
-    		    List<Integer> list=triangle.get(i);
-    			for (int j = 0; j < list.size(); j++) {
-					ans[j]=list.get(j)+(ans[j]<ans[j+1]?ans[j]:ans[j+1]);
-				}
-    		}
-		}
-    	return ans[0];
+        int[] ans=new int[triangle.get(triangle.size()-1).size()];
+        for (int i = 0; i <triangle.get(triangle.size()-1).size(); i++) {
+            ans[i]=triangle.get(triangle.size()-1).get(i);
+        }
+        if (triangle.size()>1) {
+            for (int i = triangle.size()-2; i >=0; i--) {
+                List<Integer> list=triangle.get(i);
+                for (int j = 0; j < list.size(); j++) {
+                    ans[j]=list.get(j)+(ans[j]<ans[j+1]?ans[j]:ans[j+1]);
+                }
+            }
+        }
+        return ans[0];
     }
 }
\ No newline at end of file
diff --git a/java/121. Best Time to Buy and Sell Stock.java b/java/121. Best Time to Buy and Sell Stock.java
index 6ea06de..7822c74 100644
--- a/java/121. Best Time to Buy and Sell Stock.java	
+++ b/java/121. Best Time to Buy and Sell Stock.java	
@@ -1,31 +1,31 @@
 public class Solution {
     public int maxProfit(int[] prices) {
-		if (prices.length <= 1) {
-			return 0;
-		}
-		int[] change = new int[prices.length - 1];
-		for (int i = 0; i < change.length; i++) {
-			change[i] = prices[i + 1] - prices[i];
-		}
-		int sum = 0;
-		int s = 0;
-		int begin = 0;
-		int end = 0;
-		for (int i = 0; i < change.length; i++) {
-			s += change[i];
-			if (s < 0) {
-				s = 0;
-				begin = i + 1;
-				end = i + 1;
-			}
-			if (change[i] > 0) {
-				end = i;
-			}
-			if (s > sum) {
-				sum = s;
-			}
+        if (prices.length <= 1) {
+            return 0;
+        }
+        int[] change = new int[prices.length - 1];
+        for (int i = 0; i < change.length; i++) {
+            change[i] = prices[i + 1] - prices[i];
+        }
+        int sum = 0;
+        int s = 0;
+        int begin = 0;
+        int end = 0;
+        for (int i = 0; i < change.length; i++) {
+            s += change[i];
+            if (s < 0) {
+                s = 0;
+                begin = i + 1;
+                end = i + 1;
+            }
+            if (change[i] > 0) {
+                end = i;
+            }
+            if (s > sum) {
+                sum = s;
+            }
 
-		}
-		return sum;
-	}
+        }
+        return sum;
+    }
 }
\ No newline at end of file
diff --git a/java/122. Best Time to Buy and Sell Stock II.java b/java/122. Best Time to Buy and Sell Stock II.java
index 55b8794..fd1e692 100644
--- a/java/122. Best Time to Buy and Sell Stock II.java	
+++ b/java/122. Best Time to Buy and Sell Stock II.java	
@@ -1,18 +1,18 @@
 public class Solution {
     public int maxProfit(int[] prices) {
-		if (prices.length <= 1) {
-			return 0;
-		}
-		int[] change = new int[prices.length - 1];
-		for (int i = 0; i < change.length; i++) {
-			change[i] = prices[i + 1] - prices[i];
-		}
-		int sum = 0;
-		for (int i = 0; i < change.length; i++) {
-			if (change[i]>0) {
-				sum+=change[i];
-			}
-		}
-		return sum;
-	}
+        if (prices.length <= 1) {
+            return 0;
+        }
+        int[] change = new int[prices.length - 1];
+        for (int i = 0; i < change.length; i++) {
+            change[i] = prices[i + 1] - prices[i];
+        }
+        int sum = 0;
+        for (int i = 0; i < change.length; i++) {
+            if (change[i]>0) {
+                sum+=change[i];
+            }
+        }
+        return sum;
+    }
 }
\ No newline at end of file
diff --git a/java/123. Best Time to Buy and Sell Stock III.java b/java/123. Best Time to Buy and Sell Stock III.java
index f56b221..c59add0 100644
--- a/java/123. Best Time to Buy and Sell Stock III.java	
+++ b/java/123. Best Time to Buy and Sell Stock III.java	
@@ -1,67 +1,67 @@
 public class Solution {
     public int maxProfit(int[] prices) {
-		if (prices.length <= 1) {
-			return 0;
-		}
-		int[] change = new int[prices.length - 1];
-		for (int i = 0; i < change.length; i++) {
-			change[i] = prices[i + 1] - prices[i];
-		}
-		int sum0 = 0;
-		int s0 = 0;
-		int b=0;
-		int e=0;
-		int begin0 = 0;
-		int end0 = 0;
-		for (int i = 0; i < change.length; i++) {
-			s0 += change[i];
-			if (s0 < 0) {
-				s0 = 0;
-				b=i+1;
-				e=i+1;
-			}
-			if (change[i] > 0) {
-				e=i;
-			}
-			if (s0 > sum0) {
-				sum0 = s0;
-				begin0=b;
-				end0=e;
-			}
-		}
-		int sum1 = 0;
-		int s1 = 0;
-		for (int i = 0; i <begin0; i++) {
-			s1 += change[i];
-			if (s1 < 0) {
-				s1 = 0;
-			}
-			if (s1 > sum1) {
-				sum1 = s1;
-			}
-		}
-		int sum2 = 0;
-		int s2 = 0;
-		for (int i = end0+1; i <change.length; i++) {
-			s2 += change[i];
-			if (s2 < 0) {
-				s2 = 0;
-			}
-			if (s2 > sum2) {
-				sum2 = s2;
-			}
-		}
-		int sum3 = 0;
-		int s3 = 0;
-		for (int i = begin0+1; i <end0; i++) {
-			s3 += change[i];
-			if (s3 > 0) {
-				s3 = 0;
-			}
-			if (s3 < sum3) {
-				sum3 = s3;
-			}
-		}
-		return sum0+Math.max(0-sum3, Math.max(sum1, sum2));
-	}
+        if (prices.length <= 1) {
+            return 0;
+        }
+        int[] change = new int[prices.length - 1];
+        for (int i = 0; i < change.length; i++) {
+            change[i] = prices[i + 1] - prices[i];
+        }
+        int sum0 = 0;
+        int s0 = 0;
+        int b=0;
+        int e=0;
+        int begin0 = 0;
+        int end0 = 0;
+        for (int i = 0; i < change.length; i++) {
+            s0 += change[i];
+            if (s0 < 0) {
+                s0 = 0;
+                b=i+1;
+                e=i+1;
+            }
+            if (change[i] > 0) {
+                e=i;
+            }
+            if (s0 > sum0) {
+                sum0 = s0;
+                begin0=b;
+                end0=e;
+            }
+        }
+        int sum1 = 0;
+        int s1 = 0;
+        for (int i = 0; i <begin0; i++) {
+            s1 += change[i];
+            if (s1 < 0) {
+                s1 = 0;
+            }
+            if (s1 > sum1) {
+                sum1 = s1;
+            }
+        }
+        int sum2 = 0;
+        int s2 = 0;
+        for (int i = end0+1; i <change.length; i++) {
+            s2 += change[i];
+            if (s2 < 0) {
+                s2 = 0;
+            }
+            if (s2 > sum2) {
+                sum2 = s2;
+            }
+        }
+        int sum3 = 0;
+        int s3 = 0;
+        for (int i = begin0+1; i <end0; i++) {
+            s3 += change[i];
+            if (s3 > 0) {
+                s3 = 0;
+            }
+            if (s3 < sum3) {
+                sum3 = s3;
+            }
+        }
+        return sum0+Math.max(0-sum3, Math.max(sum1, sum2));
+    }
 }
\ No newline at end of file
diff --git a/java/125. Valid Palindrome.java b/java/125. Valid Palindrome.java
index 82d4688..1d91efa 100644
--- a/java/125. Valid Palindrome.java	
+++ b/java/125. Valid Palindrome.java	
@@ -1,26 +1,26 @@
 public class Solution {
     public boolean isPalindrome(String s) {
         if (s.length()<=1) {
-			return true;
-		}
-    	char[] c=s.toCharArray();
-    	char[] nc=new char[c.length];
-    	int a=0;
-    	for (int i = 0; i < c.length; i++) {
-			if ((c[i]>96&&c[i]<123)||(c[i]>47&&c[i]<58)) {
-				nc[a]=c[i];
-				a++;
-			}
-			if (c[i]>64&&c[i]<91) {
-				nc[a]=(char) (c[i]+32);
-				a++;
-			}
-		}
-    	for (int i = 0; i < a/2; i++) {
-			if (nc[i]!=nc[a-i-1]) {
-				return false;
-			}
-		}
-    	return true;
+            return true;
+        }
+        char[] c=s.toCharArray();
+        char[] nc=new char[c.length];
+        int a=0;
+        for (int i = 0; i < c.length; i++) {
+            if ((c[i]>96&&c[i]<123)||(c[i]>47&&c[i]<58)) {
+                nc[a]=c[i];
+                a++;
+            }
+            if (c[i]>64&&c[i]<91) {
+                nc[a]=(char) (c[i]+32);
+                a++;
+            }
+        }
+        for (int i = 0; i < a/2; i++) {
+            if (nc[i]!=nc[a-i-1]) {
+                return false;
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/127. Word Ladder.java b/java/127. Word Ladder.java
index 87645c4..f6f0ce8 100644
--- a/java/127. Word Ladder.java	
+++ b/java/127. Word Ladder.java	
@@ -1,49 +1,49 @@
 public class Solution {
     public int ladderLength(String beginWord, String endWord, Set<String> wordList) {
-    	if (beginWord==null||endWord==null||wordList==null||beginWord.equals(endWord)||beginWord.length()!=endWord.length()) {
-			return 0;
-		}
-    	Map<String,List<String>> map=new HashMap<String, List<String>>();
-    	int count=1;
-    	wordList.add(beginWord);
-    	wordList.add(endWord);
-    	for (String str:wordList) {
-    		count++;
-			List<String> list=new ArrayList<String>();
-			char[] cs=str.toCharArray();
-			for (int i = 0; i < cs.length; i++) {
-				char k=cs[i];
-				for (char j = &#39;a&#39;; j <=&#39;z&#39;; j++) {
-					if (j!=k) {
-						cs[i]=j;
-						String test=String.valueOf(cs);
-						if (wordList.contains(test)) {
-							list.add(test);
-						}
-					}
-				}
-				cs[i]=k;
-			}
-			map.put(str, list);
-		}
-    	Map<String,Integer> test=new HashMap<String, Integer>();
-    	test.put(beginWord, 1);
-    	for (int i = 1; i < count; i++) {
-    		Map<String,Integer> newTest=new HashMap<String, Integer>();
-			for (String str:test.keySet()) {
-				List<String> list=map.get(str);
-				for (int j = 0; j < list.size(); j++) {
-					String k=list.get(j);
-					if (k.equals(endWord)) {
-						return i+1;
-					}
-					if (test.get(k)==null&&newTest.get(k)==null) {
-						newTest.put(k, 1);
-					}
-				}
-			}
-			test=newTest;
-		}
-    	return 0;
+        if (beginWord==null||endWord==null||wordList==null||beginWord.equals(endWord)||beginWord.length()!=endWord.length()) {
+            return 0;
+        }
+        Map<String,List<String>> map=new HashMap<String, List<String>>();
+        int count=1;
+        wordList.add(beginWord);
+        wordList.add(endWord);
+        for (String str:wordList) {
+            count++;
+            List<String> list=new ArrayList<String>();
+            char[] cs=str.toCharArray();
+            for (int i = 0; i < cs.length; i++) {
+                char k=cs[i];
+                for (char j = &#39;a&#39;; j <=&#39;z&#39;; j++) {
+                    if (j!=k) {
+                        cs[i]=j;
+                        String test=String.valueOf(cs);
+                        if (wordList.contains(test)) {
+                            list.add(test);
+                        }
+                    }
+                }
+                cs[i]=k;
+            }
+            map.put(str, list);
+        }
+        Map<String,Integer> test=new HashMap<String, Integer>();
+        test.put(beginWord, 1);
+        for (int i = 1; i < count; i++) {
+            Map<String,Integer> newTest=new HashMap<String, Integer>();
+            for (String str:test.keySet()) {
+                List<String> list=map.get(str);
+                for (int j = 0; j < list.size(); j++) {
+                    String k=list.get(j);
+                    if (k.equals(endWord)) {
+                        return i+1;
+                    }
+                    if (test.get(k)==null&&newTest.get(k)==null) {
+                        newTest.put(k, 1);
+                    }
+                }
+            }
+            test=newTest;
+        }
+        return 0;
     }
 }
\ No newline at end of file
diff --git a/java/128. Longest Consecutive Sequence.java b/java/128. Longest Consecutive Sequence.java
index 034e0fb..2caed2a 100644
--- a/java/128. Longest Consecutive Sequence.java	
+++ b/java/128. Longest Consecutive Sequence.java	
@@ -1,24 +1,24 @@
 public class Solution {
     public int longestConsecutive(int[] nums) {
-    	if (nums.length<2) {
-			return nums.length;
-		}
-    	Arrays.sort(nums);
-    	int sum=1;
-    	int length=1;
-    	for (int i = 1; i < nums.length; i++) {
-    		if (nums[i]==nums[i-1]) {
-				continue;
-			}
-			if (nums[i]==nums[i-1]+1) {
-				sum++;
-			}else {
-				if (sum>length) {
-					length=sum;
-				}
-				sum=1;
-			}
-		}
-    	return length>sum?length:sum;
+        if (nums.length<2) {
+            return nums.length;
+        }
+        Arrays.sort(nums);
+        int sum=1;
+        int length=1;
+        for (int i = 1; i < nums.length; i++) {
+            if (nums[i]==nums[i-1]) {
+                continue;
+            }
+            if (nums[i]==nums[i-1]+1) {
+                sum++;
+            }else {
+                if (sum>length) {
+                    length=sum;
+                }
+                sum=1;
+            }
+        }
+        return length>sum?length:sum;
     }
 }
\ No newline at end of file
diff --git a/java/129. Sum Root to Leaf Numbers.java b/java/129. Sum Root to Leaf Numbers.java
index 6624f63..d8dcfab 100644
--- a/java/129. Sum Root to Leaf Numbers.java	
+++ b/java/129. Sum Root to Leaf Numbers.java	
@@ -9,44 +9,44 @@
  */
 public class Solution {
     public int sumNumbers(TreeNode root) {
-    	if (root==null) {
-			return 0;
-		}
-    	List<List<TreeNode>> totalList=new ArrayList<List<TreeNode>>();
-    	List<TreeNode> initList=new ArrayList<TreeNode>();
-    	initList.add(root);
-    	totalList.add(initList);
-    	for (int i = 0; i < totalList.size(); i++) {
-    		List<TreeNode> list=totalList.get(i);
-    		TreeNode node=list.get(list.size()-1);
-    		if (node.left!=null||node.right!=null) {
-				if (node.left!=null) {
-					List<TreeNode> newList=new ArrayList<TreeNode>();
-					newList.addAll(list);
-					newList.add(node.left);
-					totalList.add(newList);
-				}
-				if (node.right!=null) {
-					List<TreeNode> newList=new ArrayList<TreeNode>();
-					newList.addAll(list);
-					newList.add(node.right);
-					totalList.add(newList);
-				}
-				totalList.remove(i);
-				i--;
-			}
-		}
-    	long answer=0;
-    	for (int i = 0; i < totalList.size(); i++) {
-    		List<TreeNode> list=totalList.get(i);
-    		long sum=0;
-			for (int j = 0; j < list.size(); j++) {
-				sum+=list.get(j).val;
-				sum*=10;
-			}
-			sum/=10;
-			answer+=sum;
-		}
-    	return Integer.valueOf(""+answer);
+        if (root==null) {
+            return 0;
+        }
+        List<List<TreeNode>> totalList=new ArrayList<List<TreeNode>>();
+        List<TreeNode> initList=new ArrayList<TreeNode>();
+        initList.add(root);
+        totalList.add(initList);
+        for (int i = 0; i < totalList.size(); i++) {
+            List<TreeNode> list=totalList.get(i);
+            TreeNode node=list.get(list.size()-1);
+            if (node.left!=null||node.right!=null) {
+                if (node.left!=null) {
+                    List<TreeNode> newList=new ArrayList<TreeNode>();
+                    newList.addAll(list);
+                    newList.add(node.left);
+                    totalList.add(newList);
+                }
+                if (node.right!=null) {
+                    List<TreeNode> newList=new ArrayList<TreeNode>();
+                    newList.addAll(list);
+                    newList.add(node.right);
+                    totalList.add(newList);
+                }
+                totalList.remove(i);
+                i--;
+            }
+        }
+        long answer=0;
+        for (int i = 0; i < totalList.size(); i++) {
+            List<TreeNode> list=totalList.get(i);
+            long sum=0;
+            for (int j = 0; j < list.size(); j++) {
+                sum+=list.get(j).val;
+                sum*=10;
+            }
+            sum/=10;
+            answer+=sum;
+        }
+        return Integer.valueOf(""+answer);
     }
 }
\ No newline at end of file
diff --git a/java/131. Palindrome Partitioning.java b/java/131. Palindrome Partitioning.java
index 191cc3e..3679115 100644
--- a/java/131. Palindrome Partitioning.java	
+++ b/java/131. Palindrome Partitioning.java	
@@ -1,42 +1,42 @@
 public class Solution {
-	Map<String,List<List<String>>> map=new HashMap<String, List<List<String>>>();
+    Map<String,List<List<String>>> map=new HashMap<String, List<List<String>>>();
     public List<List<String>> partition(String s) {
         if (map.get(s)!=null) {
-        	return map.get(s);
-		}
+            return map.get(s);
+        }
         List<List<String>> ans=new ArrayList<List<String>>();
         if(isPartition(s)){
-        	List<String> list=new ArrayList<String>();
-        	list.add(s);
-        	ans.add(list);
+            List<String> list=new ArrayList<String>();
+            list.add(s);
+            ans.add(list);
         }
         for (int i = 0; i < s.length()-1; i++) {
-			String k=s.substring(0,i+1);
-			if (isPartition(k)) {
-				String t=s.substring(i+1,s.length());
-				List<List<String>> list=partition(t);
-				for (int j = 0; j < list.size(); j++) {
-					List<String> l=new ArrayList<String>();
-					l.add(k);
-					l.addAll(list.get(j));
-					ans.add(l);
-				}
- 			}
-		}
-    	map.put(s, ans);
-    	return ans;
+            String k=s.substring(0,i+1);
+            if (isPartition(k)) {
+                String t=s.substring(i+1,s.length());
+                List<List<String>> list=partition(t);
+                for (int j = 0; j < list.size(); j++) {
+                    List<String> l=new ArrayList<String>();
+                    l.add(k);
+                    l.addAll(list.get(j));
+                    ans.add(l);
+                }
+             }
+        }
+        map.put(s, ans);
+        return ans;
     }
     public boolean isPartition(String s){
-    	if(s.length()==1){
-    		return true;
-    	}
-    	char[] c=s.toCharArray();
-    	int length=c.length;
-    	for (int i = 0; i < length/2; i++) {
-			if(c[i]!=c[length-1-i]){
-				return false;
-			}
-		}
-    	return true;
+        if(s.length()==1){
+            return true;
+        }
+        char[] c=s.toCharArray();
+        int length=c.length;
+        for (int i = 0; i < length/2; i++) {
+            if(c[i]!=c[length-1-i]){
+                return false;
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/133. Clone Graph.java b/java/133. Clone Graph.java
index a6f1569..d985706 100644
--- a/java/133. Clone Graph.java	
+++ b/java/133. Clone Graph.java	
@@ -8,45 +8,45 @@
  */
 public class Solution {
     public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) {
-    	if (node!=null) {
-    		Map<UndirectedGraphNode, Integer> initMap=f(node,new HashMap<UndirectedGraphNode, Integer>());
-    		Map<UndirectedGraphNode, Integer> map=new HashMap<UndirectedGraphNode, Integer>();
-    		map.put(node, 0);
-    		List<UndirectedGraphNode> list=new ArrayList<UndirectedGraphNode>();
-    		list.add(node);
-    		List<UndirectedGraphNode> ans=new ArrayList<UndirectedGraphNode>();
-    		UndirectedGraphNode init=new UndirectedGraphNode(node.label);
-    		ans.add(init);
-    		int k=1;
-    		for (UndirectedGraphNode ugn : initMap.keySet()) {
-    			if (ugn!=node) {
-					map.put(ugn, k);
-					list.add(ugn);
-					ans.add(new UndirectedGraphNode(ugn.label));
-					k++;
-				}
-    		}
-    		for (int i = 0; i < list.size(); i++) {
-				List<UndirectedGraphNode> neis=list.get(i).neighbors;
-				UndirectedGraphNode u=ans.get(i);
-				for (int j = 0; j < neis.size(); j++) {
-					u.neighbors.add(ans.get(map.get(neis.get(j))));
-				}
-			}
-    		return init;
-		}
-    	return null;
+        if (node!=null) {
+            Map<UndirectedGraphNode, Integer> initMap=f(node,new HashMap<UndirectedGraphNode, Integer>());
+            Map<UndirectedGraphNode, Integer> map=new HashMap<UndirectedGraphNode, Integer>();
+            map.put(node, 0);
+            List<UndirectedGraphNode> list=new ArrayList<UndirectedGraphNode>();
+            list.add(node);
+            List<UndirectedGraphNode> ans=new ArrayList<UndirectedGraphNode>();
+            UndirectedGraphNode init=new UndirectedGraphNode(node.label);
+            ans.add(init);
+            int k=1;
+            for (UndirectedGraphNode ugn : initMap.keySet()) {
+                if (ugn!=node) {
+                    map.put(ugn, k);
+                    list.add(ugn);
+                    ans.add(new UndirectedGraphNode(ugn.label));
+                    k++;
+                }
+            }
+            for (int i = 0; i < list.size(); i++) {
+                List<UndirectedGraphNode> neis=list.get(i).neighbors;
+                UndirectedGraphNode u=ans.get(i);
+                for (int j = 0; j < neis.size(); j++) {
+                    u.neighbors.add(ans.get(map.get(neis.get(j))));
+                }
+            }
+            return init;
+        }
+        return null;
     }
     public Map<UndirectedGraphNode, Integer> f(UndirectedGraphNode node,Map<UndirectedGraphNode, Integer> map){
-    	if (node!=null&&map.get(node)==null) {
-    		map.put(node, 1);
-    		List<UndirectedGraphNode> list=node.neighbors;
-    		if (list!=null) {
-				for (int i = 0; i < list.size(); i++) {
-					map=f(list.get(i),map);
-				}
-			}
-		}
-    	return map;
+        if (node!=null&&map.get(node)==null) {
+            map.put(node, 1);
+            List<UndirectedGraphNode> list=node.neighbors;
+            if (list!=null) {
+                for (int i = 0; i < list.size(); i++) {
+                    map=f(list.get(i),map);
+                }
+            }
+        }
+        return map;
     }
 }
\ No newline at end of file
diff --git a/java/134. Gas Station.java b/java/134. Gas Station.java
index 83330fe..0dfdc58 100644
--- a/java/134. Gas Station.java	
+++ b/java/134. Gas Station.java	
@@ -1,23 +1,23 @@
 public class Solution {
     public int canCompleteCircuit(int[] gas, int[] cost) {
-		int[] n = new int[gas.length];
-		for (int i = 0; i < n.length; i++) {
-			n[i] = gas[i] - cost[i];
-		}
-		int sum = 0;
-		int begin = 0;
-		int truebegin=0;
-		for (int i = 0; i < n.length*2; i++) {
-			sum += n[i%n.length];
-			while (sum < 0) {
-				sum -= n[truebegin];
-				begin++;
-				truebegin=begin%n.length;
-			}
-			if (i-begin>=n.length) {
-				return truebegin;
-			}
-		}
-		return -1;
-	}
+        int[] n = new int[gas.length];
+        for (int i = 0; i < n.length; i++) {
+            n[i] = gas[i] - cost[i];
+        }
+        int sum = 0;
+        int begin = 0;
+        int truebegin=0;
+        for (int i = 0; i < n.length*2; i++) {
+            sum += n[i%n.length];
+            while (sum < 0) {
+                sum -= n[truebegin];
+                begin++;
+                truebegin=begin%n.length;
+            }
+            if (i-begin>=n.length) {
+                return truebegin;
+            }
+        }
+        return -1;
+    }
 }
\ No newline at end of file
diff --git a/java/135. Candy.java b/java/135. Candy.java
index 01ae341..5e6b7f5 100644
--- a/java/135. Candy.java	
+++ b/java/135. Candy.java	
@@ -5,21 +5,21 @@ public int candy(int[] ratings) {
         candies[0]=1;
         //��������ɨ�裬����Ҳ�������������1��������ֻ��1����
         for (int i = 1; i < ratings.length; i++) {
-			if (ratings[i]>ratings[i-1]) {
-				candies[i]=candies[i-1]+1;
-			}else {
-				candies[i]=1;
-			}
-		}
+            if (ratings[i]>ratings[i-1]) {
+                candies[i]=candies[i-1]+1;
+            }else {
+                candies[i]=1;
+            }
+        }
         for (int i = length - 2; i >= 0; i--) {  
             if (ratings[i]>ratings[i+1]&&candies[i]<=candies[i+1]) {  
-            	candies[i] = candies[i+1]+1;  
+                candies[i] = candies[i+1]+1;  
             }  
         }
         int ans=0;
         for (int i = 0; i <length; i++) {
-			ans+=candies[i];
-		}
-    	return ans;
+            ans+=candies[i];
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/136. Single Number.java b/java/136. Single Number.java
index 33dcae4..4c9938f 100644
--- a/java/136. Single Number.java	
+++ b/java/136. Single Number.java	
@@ -1,9 +1,9 @@
 public class Solution {
     public int singleNumber(int[] nums) {
-    	int answer=0;
-    	for (int i = 0; i < nums.length; i++) {
-			answer^=nums[i];
-		}
-    	return answer;
+        int answer=0;
+        for (int i = 0; i < nums.length; i++) {
+            answer^=nums[i];
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/137. Single Number II.java b/java/137. Single Number II.java
index e4d0e94..a9adad9 100644
--- a/java/137. Single Number II.java	
+++ b/java/137. Single Number II.java	
@@ -1,20 +1,20 @@
 public class Solution {
     public int singleNumber(int[] nums) {
-    	int min=Integer.MIN_VALUE;
-    	int ans=0;
-    	for (int i = 0; i < 32; i++) {
-    		int sum=0;
-			for (int j = 0; j < nums.length; j++) {
-				if ((nums[j]&min)!=0) {
-					sum++;
-				}
-				nums[j]<<=1;
-			}
-			ans+=sum%3;
-			if (i!=31) {
-				ans<<=1;
-			}
-		}
-    	return ans;
+        int min=Integer.MIN_VALUE;
+        int ans=0;
+        for (int i = 0; i < 32; i++) {
+            int sum=0;
+            for (int j = 0; j < nums.length; j++) {
+                if ((nums[j]&min)!=0) {
+                    sum++;
+                }
+                nums[j]<<=1;
+            }
+            ans+=sum%3;
+            if (i!=31) {
+                ans<<=1;
+            }
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/138. Copy List with Random Pointer.java b/java/138. Copy List with Random Pointer.java
index 7aad516..bc828b8 100644
--- a/java/138. Copy List with Random Pointer.java	
+++ b/java/138. Copy List with Random Pointer.java	
@@ -8,16 +8,16 @@
  */
 public class Solution {
     public RandomListNode copyRandomList(RandomListNode head) {
-    	RandomListNode answer=null;
-    	if (head!=null) {
-			answer=new RandomListNode(head.label);
-		}else {
-			return null;
-		}
-    	if (head.random!=null) {
-    		answer.random=new RandomListNode(head.random.label);
-		}
-    	answer.next=copyRandomList(head.next);
-    	return answer;
+        RandomListNode answer=null;
+        if (head!=null) {
+            answer=new RandomListNode(head.label);
+        }else {
+            return null;
+        }
+        if (head.random!=null) {
+            answer.random=new RandomListNode(head.random.label);
+        }
+        answer.next=copyRandomList(head.next);
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/139. Word Break.java b/java/139. Word Break.java
index 4320a84..ee88606 100644
--- a/java/139. Word Break.java	
+++ b/java/139. Word Break.java	
@@ -1,28 +1,28 @@
 public class Solution {
     public boolean wordBreak(String s, Set<String> wordDict) {
-    	return f(s,wordDict,new HashMap<String, Boolean>());
+        return f(s,wordDict,new HashMap<String, Boolean>());
     }
     public boolean f(String s, Set<String> wordDict,Map<String, Boolean> map){
         if (s==null||s.length()==0) {
-			return true;
-		}
-    	if (map.get(s)!=null) {
-			return map.get(s);
-		}else {
-			for (int i = 0; i < s.length(); i++) {
-				String str=s.substring(0,i+1);
-				boolean flag=false;
-				for (String test : wordDict) {
-					if (str.equals(test)) {
-						flag=true;
-						if (f(s.substring(i+1,s.length()),wordDict,map)) {
-							return true;
-						}
-					}
-				}
-				map.put(str, flag);
-			}
-	    	return false;
-		}
+            return true;
+        }
+        if (map.get(s)!=null) {
+            return map.get(s);
+        }else {
+            for (int i = 0; i < s.length(); i++) {
+                String str=s.substring(0,i+1);
+                boolean flag=false;
+                for (String test : wordDict) {
+                    if (str.equals(test)) {
+                        flag=true;
+                        if (f(s.substring(i+1,s.length()),wordDict,map)) {
+                            return true;
+                        }
+                    }
+                }
+                map.put(str, flag);
+            }
+            return false;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/140. Word Break II.java b/java/140. Word Break II.java
index 207465a..11c70da 100644
--- a/java/140. Word Break II.java	
+++ b/java/140. Word Break II.java	
@@ -1,46 +1,46 @@
 public class Solution {
-	Map<String,List<String>> map=new HashMap<String, List<String>>();
-	Map<String,Boolean> bmap=new HashMap<String, Boolean>();
+    Map<String,List<String>> map=new HashMap<String, List<String>>();
+    Map<String,Boolean> bmap=new HashMap<String, Boolean>();
     public List<String> wordBreak(String s, Set<String> wordDict) {
-    	List<String> list=new ArrayList<String>();
-    	if(s==null||s.length()==0){
-    		return list;
-    	}
-    	if (map.get(s)!=null) {
-			return map.get(s);
-		}
-    	if(bmap.get(s)!=null){
-    		return null;
-    	}
-    	for (int i = 0; i < s.length()-1; i++) {
-			String k=s.substring(0,i+1);
-			if(wordDict.contains(k)){
-				String t=s.substring(i+1,s.length());
-				if(bmap.get(t)==null){
-					List<String> l=map.get(t);
-					if (l!=null) {
-						for (int j = 0; j < l.size(); j++) {
-							list.add(k+" "+l.get(j));
-						}
-					}else {
-						List<String> a=wordBreak(t,wordDict);
-						if (a!=null) {
-							for (int j = 0; j < a.size(); j++) {
-								list.add(k+" "+a.get(j));
-							}
-						}
-					}
-				}
-			}
-		}
-    	if(wordDict.contains(s)){
-    		list.add(s);
-    	}
-    	if (list.size()==0) {
-    		bmap.put(s, false);
-			return list;
-		}
-    	map.put(s, list);
-    	return list;
+        List<String> list=new ArrayList<String>();
+        if(s==null||s.length()==0){
+            return list;
+        }
+        if (map.get(s)!=null) {
+            return map.get(s);
+        }
+        if(bmap.get(s)!=null){
+            return null;
+        }
+        for (int i = 0; i < s.length()-1; i++) {
+            String k=s.substring(0,i+1);
+            if(wordDict.contains(k)){
+                String t=s.substring(i+1,s.length());
+                if(bmap.get(t)==null){
+                    List<String> l=map.get(t);
+                    if (l!=null) {
+                        for (int j = 0; j < l.size(); j++) {
+                            list.add(k+" "+l.get(j));
+                        }
+                    }else {
+                        List<String> a=wordBreak(t,wordDict);
+                        if (a!=null) {
+                            for (int j = 0; j < a.size(); j++) {
+                                list.add(k+" "+a.get(j));
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        if(wordDict.contains(s)){
+            list.add(s);
+        }
+        if (list.size()==0) {
+            bmap.put(s, false);
+            return list;
+        }
+        map.put(s, list);
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/141. Linked List Cycle.java b/java/141. Linked List Cycle.java
index a31fa63..7ffa958 100644
--- a/java/141. Linked List Cycle.java	
+++ b/java/141. Linked List Cycle.java	
@@ -11,17 +11,17 @@
  */
 public class Solution {
     public boolean hasCycle(ListNode head) {
-    	ListNode fast=head;
-    	ListNode slow=head;
+        ListNode fast=head;
+        ListNode slow=head;
         while (true) {
-			if (fast==null||fast.next==null||slow==null) {
-				return false;
-			}
-			fast=fast.next.next;
-			slow=slow.next;
-			if (fast==slow) {
-				return true;
-			}
-		}
+            if (fast==null||fast.next==null||slow==null) {
+                return false;
+            }
+            fast=fast.next.next;
+            slow=slow.next;
+            if (fast==slow) {
+                return true;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/142. Linked List Cycle II.java b/java/142. Linked List Cycle II.java
index 66bc838..82014a7 100644
--- a/java/142. Linked List Cycle II.java	
+++ b/java/142. Linked List Cycle II.java	
@@ -11,25 +11,25 @@
  */
 public class Solution {
     public ListNode detectCycle(ListNode head) {
-    	ListNode fast=head;
-    	ListNode slow=head;
+        ListNode fast=head;
+        ListNode slow=head;
         while (true) {
-			if (fast==null||fast.next==null) {
-				return null;
-			}
-			fast=fast.next.next;
-			slow=slow.next;
-			if (fast==slow) {
-				ListNode again=head;
-				while (true) {
-					if (slow==again) {
-						return again;
-					}else {
-						slow=slow.next;
-						again=again.next;
-					}
-				}
-			}
-		}
+            if (fast==null||fast.next==null) {
+                return null;
+            }
+            fast=fast.next.next;
+            slow=slow.next;
+            if (fast==slow) {
+                ListNode again=head;
+                while (true) {
+                    if (slow==again) {
+                        return again;
+                    }else {
+                        slow=slow.next;
+                        again=again.next;
+                    }
+                }
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/143. Reorder List.java b/java/143. Reorder List.java
index 73f90bf..41c55ae 100644
--- a/java/143. Reorder List.java	
+++ b/java/143. Reorder List.java	
@@ -8,21 +8,21 @@
  */
 public class Solution {
     public void reorderList(ListNode head) {
-		if (head!=null) {
-			List<ListNode> list = zuhe(head, new ArrayList<ListNode>());
-			int l=list.size();
-			for (int i = 0; i < l/2; i++) {
-				list.get(i).next = list.get(l - 1 - i);
-				list.get(l - 1 - i).next = list.get(i + 1);
-			}
-			list.get(l/2).next = null;
-		}
-	}
-	public List<ListNode> zuhe(ListNode head, List<ListNode> list) {
-		while (head!=null) {
-			list.add(head);
-			head=head.next;
-		}
-		return list;
-	}
+        if (head!=null) {
+            List<ListNode> list = zuhe(head, new ArrayList<ListNode>());
+            int l=list.size();
+            for (int i = 0; i < l/2; i++) {
+                list.get(i).next = list.get(l - 1 - i);
+                list.get(l - 1 - i).next = list.get(i + 1);
+            }
+            list.get(l/2).next = null;
+        }
+    }
+    public List<ListNode> zuhe(ListNode head, List<ListNode> list) {
+        while (head!=null) {
+            list.add(head);
+            head=head.next;
+        }
+        return list;
+    }
 }
\ No newline at end of file
diff --git a/java/144. Binary Tree Preorder Traversal.java b/java/144. Binary Tree Preorder Traversal.java
index bcd91e4..f9d6a11 100644
--- a/java/144. Binary Tree Preorder Traversal.java	
+++ b/java/144. Binary Tree Preorder Traversal.java	
@@ -9,16 +9,16 @@
  */
 public class Solution {
     public List<Integer> preorderTraversal(TreeNode root) {
-    	List<Integer> list=new ArrayList<Integer>();
+        List<Integer> list=new ArrayList<Integer>();
         return preorder(root,list);
     }
     public List<Integer> preorder(TreeNode root,List<Integer> list){
-    	if (root==null) {
-			return list;
-		}
-    	list.add(root.val);
-    	list=preorder(root.left,list);
-    	list=preorder(root.right, list);
-    	return list;
+        if (root==null) {
+            return list;
+        }
+        list.add(root.val);
+        list=preorder(root.left,list);
+        list=preorder(root.right, list);
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/145. Binary Tree Postorder Traversal.java b/java/145. Binary Tree Postorder Traversal.java
index 316f6ce..5d26b5d 100644
--- a/java/145. Binary Tree Postorder Traversal.java	
+++ b/java/145. Binary Tree Postorder Traversal.java	
@@ -9,16 +9,16 @@
  */
 public class Solution {
     public List<Integer> postorderTraversal(TreeNode root) {
-    	List<Integer> list=new ArrayList<Integer>();
+        List<Integer> list=new ArrayList<Integer>();
         return postorder(root,list);
     }
     public List<Integer> postorder(TreeNode root,List<Integer> list){
-    	if (root==null) {
-			return list;
-		}
-    	list=postorder(root.left,list);
-    	list=postorder(root.right, list);
-    	list.add(root.val);
-    	return list;
+        if (root==null) {
+            return list;
+        }
+        list=postorder(root.left,list);
+        list=postorder(root.right, list);
+        list.add(root.val);
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/147. Insertion Sort List.java b/java/147. Insertion Sort List.java
index ef396b1..21443d2 100644
--- a/java/147. Insertion Sort List.java	
+++ b/java/147. Insertion Sort List.java	
@@ -8,29 +8,29 @@
  */
 public class Solution {
     public ListNode insertionSortList(ListNode head) {
-    	if (head==null||head.next==null) {
-			return head;
-		}
+        if (head==null||head.next==null) {
+            return head;
+        }
         ListNode node=head.next;
         ListNode ans=new ListNode(head.val);
         while (node!=null) {
-			if (node.val<=ans.val) {
-				ListNode newAns=new ListNode(node.val);
-				newAns.next=ans;
-				ans=newAns;
-			}else {
-				ListNode test=ans;
-				ListNode a=null;
-				while (test!=null&&test.val<node.val) {
-					a=test;
-					test=test.next;
-				}
-				ListNode insert=new ListNode(node.val);
-				a.next=insert;
-				insert.next=test;
-			}
-			node=node.next;
-		}
+            if (node.val<=ans.val) {
+                ListNode newAns=new ListNode(node.val);
+                newAns.next=ans;
+                ans=newAns;
+            }else {
+                ListNode test=ans;
+                ListNode a=null;
+                while (test!=null&&test.val<node.val) {
+                    a=test;
+                    test=test.next;
+                }
+                ListNode insert=new ListNode(node.val);
+                a.next=insert;
+                insert.next=test;
+            }
+            node=node.next;
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/148. Sort List.java b/java/148. Sort List.java
index d8edde6..5579e15 100644
--- a/java/148. Sort List.java	
+++ b/java/148. Sort List.java	
@@ -8,37 +8,37 @@
  */
 public class Solution {
     public ListNode sortList(ListNode head) {
-    	if (head==null||head.next==null) {
-			return head;
-		}
+        if (head==null||head.next==null) {
+            return head;
+        }
         ListNode mid=getMid(head);
         ListNode next=mid.next;
         mid.next=null;
-    	return merge(sortList(head),sortList(next));
+        return merge(sortList(head),sortList(next));
     }
     public ListNode getMid(ListNode head){
-    	ListNode fast=head;
-    	ListNode slow=head;
-    	while(fast.next!=null&&fast.next.next!=null) {  
+        ListNode fast=head;
+        ListNode slow=head;
+        while(fast.next!=null&&fast.next.next!=null) {  
             slow = slow.next;  
             fast = fast.next.next;  
         }  
-    	return slow;
+        return slow;
     }
     public ListNode merge(ListNode a,ListNode b){
-    	ListNode ans=new ListNode(0);
-    	ListNode node=ans;
-    	while (a!=null&&b!=null) {
-    		if (a.val<b.val) {
-				node.next=a;
-				a=a.next;
-			}else {
-				node.next=b;
-				b=b.next;
-			}
-    		node=node.next;
-		}
-    	node.next=a==null?b:a;
-    	return ans.next;
+        ListNode ans=new ListNode(0);
+        ListNode node=ans;
+        while (a!=null&&b!=null) {
+            if (a.val<b.val) {
+                node.next=a;
+                a=a.next;
+            }else {
+                node.next=b;
+                b=b.next;
+            }
+            node=node.next;
+        }
+        node.next=a==null?b:a;
+        return ans.next;
     }
 }
\ No newline at end of file
diff --git a/java/149. Max Points on a Line.java b/java/149. Max Points on a Line.java
index f6b84fa..78faa84 100644
--- a/java/149. Max Points on a Line.java	
+++ b/java/149. Max Points on a Line.java	
@@ -10,37 +10,37 @@
 public class Solution {
     public int maxPoints(Point[] points) {
         if (points.length<3) {
-			return points.length;
-		}
+            return points.length;
+        }
         int answer=2;
-    	for (int i = 0; i < points.length; i++) {
-			for (int j = i+1; j < points.length; j++) {
-				if((points[i].x!=points[j].x)||(points[i].y!=points[j].y)){
-					int sum=0;
-					for (int k = 0; k < points.length; k++) {
-						if (isStraight(points[i],points[j],points[k])) {
-							sum++;
-						}
-					}
-					if (sum>answer) {
-						answer=sum;
-					}
-				}else {
-					int sum=0;
-					for (int k = 0; k < points.length; k++) {
-						if ((points[k].x==points[j].x)&&(points[k].y==points[j].y)) {
-							sum++;
-						}
-					}
-					if (sum>answer) {
-						answer=sum;
-					}
-				}
-			}
-		}
-    	return answer;
+        for (int i = 0; i < points.length; i++) {
+            for (int j = i+1; j < points.length; j++) {
+                if((points[i].x!=points[j].x)||(points[i].y!=points[j].y)){
+                    int sum=0;
+                    for (int k = 0; k < points.length; k++) {
+                        if (isStraight(points[i],points[j],points[k])) {
+                            sum++;
+                        }
+                    }
+                    if (sum>answer) {
+                        answer=sum;
+                    }
+                }else {
+                    int sum=0;
+                    for (int k = 0; k < points.length; k++) {
+                        if ((points[k].x==points[j].x)&&(points[k].y==points[j].y)) {
+                            sum++;
+                        }
+                    }
+                    if (sum>answer) {
+                        answer=sum;
+                    }
+                }
+            }
+        }
+        return answer;
     }
     public boolean isStraight (Point a,Point b,Point c){
-    	return ((b.y-c.y)*(a.x-c.x))==((a.y-c.y)*(b.x-c.x));
+        return ((b.y-c.y)*(a.x-c.x))==((a.y-c.y)*(b.x-c.x));
     }
 }
\ No newline at end of file
diff --git a/java/150. Evaluate Reverse Polish Notation.java b/java/150. Evaluate Reverse Polish Notation.java
index 8a4e316..5ce6496 100644
--- a/java/150. Evaluate Reverse Polish Notation.java	
+++ b/java/150. Evaluate Reverse Polish Notation.java	
@@ -1,39 +1,39 @@
 public class Solution {
     public int evalRPN(String[] tokens) {
-		List<Integer> list = new ArrayList<Integer>();
-		for (int i = 0; i < tokens.length; i++) {
-			if (tokens[i].equals("+")) {
-				int b = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int a = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int sum = a + b;
-				list.add(sum);
-			} else if (tokens[i].equals("-")) {
-				int b = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int a = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int sum = a - b;
-				list.add(sum);
-			} else if (tokens[i].equals("*")) {
-				int b = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int a = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int sum = a * b;
-				list.add(sum);
-			} else if (tokens[i].equals("/")) {
-				int b = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int a = list.get(list.size() - 1);
-				list.remove(list.size() - 1);
-				int sum = a / b;
-				list.add(sum);
-			} else {
-				list.add(Integer.parseInt(tokens[i]));
-			}
-		}
-		return list.get(0);
-	}
+        List<Integer> list = new ArrayList<Integer>();
+        for (int i = 0; i < tokens.length; i++) {
+            if (tokens[i].equals("+")) {
+                int b = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int a = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int sum = a + b;
+                list.add(sum);
+            } else if (tokens[i].equals("-")) {
+                int b = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int a = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int sum = a - b;
+                list.add(sum);
+            } else if (tokens[i].equals("*")) {
+                int b = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int a = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int sum = a * b;
+                list.add(sum);
+            } else if (tokens[i].equals("/")) {
+                int b = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int a = list.get(list.size() - 1);
+                list.remove(list.size() - 1);
+                int sum = a / b;
+                list.add(sum);
+            } else {
+                list.add(Integer.parseInt(tokens[i]));
+            }
+        }
+        return list.get(0);
+    }
 }
\ No newline at end of file
diff --git a/java/151. Reverse Words in a String.java b/java/151. Reverse Words in a String.java
index 9cb9f17..1a80890 100644
--- a/java/151. Reverse Words in a String.java	
+++ b/java/151. Reverse Words in a String.java	
@@ -1,42 +1,42 @@
 public class Solution {
     public String reverseWords(String s) {
-		if (s.length()<1) {
-			return s;
-		}
-		String a = "";
-		String answer = "";
-		boolean flag=true;
-		for (int i = s.length() - 1; i >= 0; i--) {
-			String k = s.substring(i, i + 1);
-			if (flag) {
-				if (k.equals(" ")) {
-					
-				}else {
-					flag=false;
-					a=k+a;
-				}
-			}else {
-				if (k.equals(" ")) {
-					flag=true;
-					answer=answer+" "+a;
-					a="";
-				}else {
-					a=k+a;
-				}
-			}
-		}
-		if (a.length()!=0) {
-				answer=answer+" "+a;
-		}
-		if (answer.length()==0) {
-				return "";
-			}
-		while (answer.substring(0,1).equals(" ")) {
-		    if (answer.length()==1) {
-				return "";
-			}
-		    answer=answer.substring(1, answer.length());
-		}
-		return answer;
-	}
+        if (s.length()<1) {
+            return s;
+        }
+        String a = "";
+        String answer = "";
+        boolean flag=true;
+        for (int i = s.length() - 1; i >= 0; i--) {
+            String k = s.substring(i, i + 1);
+            if (flag) {
+                if (k.equals(" ")) {
+                    
+                }else {
+                    flag=false;
+                    a=k+a;
+                }
+            }else {
+                if (k.equals(" ")) {
+                    flag=true;
+                    answer=answer+" "+a;
+                    a="";
+                }else {
+                    a=k+a;
+                }
+            }
+        }
+        if (a.length()!=0) {
+                answer=answer+" "+a;
+        }
+        if (answer.length()==0) {
+                return "";
+            }
+        while (answer.substring(0,1).equals(" ")) {
+            if (answer.length()==1) {
+                return "";
+            }
+            answer=answer.substring(1, answer.length());
+        }
+        return answer;
+    }
 }
diff --git a/java/152. Maximum Product Subarray.java b/java/152. Maximum Product Subarray.java
index 455108e..caa9601 100644
--- a/java/152. Maximum Product Subarray.java	
+++ b/java/152. Maximum Product Subarray.java	
@@ -4,70 +4,70 @@ public int maxProduct(int[] nums) {
         List<Integer> list=new ArrayList<Integer>();
         boolean flag=false;
         for (int i = 0; i < nums.length; i++) {
-			if (nums[i]!=0) {
-				list.add(nums[i]);
-			}else {
-			    flag=true;
-				if (list.size()!=0) {
-					totalList.add(list);
-				}
-				list=new ArrayList<Integer>();
-			}
-		}
+            if (nums[i]!=0) {
+                list.add(nums[i]);
+            }else {
+                flag=true;
+                if (list.size()!=0) {
+                    totalList.add(list);
+                }
+                list=new ArrayList<Integer>();
+            }
+        }
         if (list.size()!=0) {
-			totalList.add(list);
-		}
+            totalList.add(list);
+        }
         if (totalList.size()==0) {
-			return 0;
-		}
+            return 0;
+        }
         int ans=Integer.MIN_VALUE;
-    	for (int i = 0; i < totalList.size(); i++) {
-    		int f=max(totalList.get(i));
-			if (f>ans) {
-				ans=f;
-			}
-		}
-		if (flag&&ans<0) {
-			return 0;
-		}
-    	return ans;
+        for (int i = 0; i < totalList.size(); i++) {
+            int f=max(totalList.get(i));
+            if (f>ans) {
+                ans=f;
+            }
+        }
+        if (flag&&ans<0) {
+            return 0;
+        }
+        return ans;
     }
     
     public int max(List<Integer> list){ 
-    	if (list.size()==1) {
-			return list.get(0);
-		}
-    	int s=-1;
-    	int e=-1;
-    	int sum=0;
-    	for (int i = 0; i <list.size(); i++) {
-			if (list.get(i)<0) {
-				if (s<0) {
-					s=i;
-				}else {
-					e=i;
-				}
-				sum++;
-			}
-		}
-    	if (e==-1) {
-			e=s;
-		}
-    	int ans=1;
-    	for (int i = 0; i <list.size(); i++) {
-			ans*=list.get(i);
-		}
-    	if (sum%2==0) {
-			return ans;
-		}
-    	int left=1;
-    	for (int i = 0; i <=s; i++) {
-			left*=list.get(i);
-		}
-    	int right=1;
-    	for (int i = list.size()-1; i >=e; i--) {
-			right*=list.get(i);
-		}
-    	return left>right?(ans/left):(ans/right);
+        if (list.size()==1) {
+            return list.get(0);
+        }
+        int s=-1;
+        int e=-1;
+        int sum=0;
+        for (int i = 0; i <list.size(); i++) {
+            if (list.get(i)<0) {
+                if (s<0) {
+                    s=i;
+                }else {
+                    e=i;
+                }
+                sum++;
+            }
+        }
+        if (e==-1) {
+            e=s;
+        }
+        int ans=1;
+        for (int i = 0; i <list.size(); i++) {
+            ans*=list.get(i);
+        }
+        if (sum%2==0) {
+            return ans;
+        }
+        int left=1;
+        for (int i = 0; i <=s; i++) {
+            left*=list.get(i);
+        }
+        int right=1;
+        for (int i = list.size()-1; i >=e; i--) {
+            right*=list.get(i);
+        }
+        return left>right?(ans/left):(ans/right);
     }
 }
\ No newline at end of file
diff --git a/java/153. Find Minimum in Rotated Sorted Array.java b/java/153. Find Minimum in Rotated Sorted Array.java
index bd04554..8ce0764 100644
--- a/java/153. Find Minimum in Rotated Sorted Array.java	
+++ b/java/153. Find Minimum in Rotated Sorted Array.java	
@@ -4,14 +4,14 @@ public int findMin(int[] nums) {
         int end=nums.length-1;
         int half=(begin+end)/2;
         while (end-begin>1) {
-			if (nums[half]>nums[begin]&&nums[half]>nums[end]) {
-				begin=half;
-				half=(begin+end)/2;
-			}else {
-				end=half;
-				half=(begin+end)/2;
-			}
-		}
-    	return nums[begin]>nums[end]?nums[end]:nums[begin];
+            if (nums[half]>nums[begin]&&nums[half]>nums[end]) {
+                begin=half;
+                half=(begin+end)/2;
+            }else {
+                end=half;
+                half=(begin+end)/2;
+            }
+        }
+        return nums[begin]>nums[end]?nums[end]:nums[begin];
     }
 }
\ No newline at end of file
diff --git a/java/154. Find Minimum in Rotated Sorted Array II.java b/java/154. Find Minimum in Rotated Sorted Array II.java
index 0102d52..da52486 100644
--- a/java/154. Find Minimum in Rotated Sorted Array II.java	
+++ b/java/154. Find Minimum in Rotated Sorted Array II.java	
@@ -1,11 +1,11 @@
 public class Solution {
     public int findMin(int[] nums) {
-    	int a=nums[0];
-    	for (int i = 1; i < nums.length; i++) {
-			if (nums[i]<a) {
-				a=nums[i];
-			}
-		}
-    	return a;
+        int a=nums[0];
+        for (int i = 1; i < nums.length; i++) {
+            if (nums[i]<a) {
+                a=nums[i];
+            }
+        }
+        return a;
     }
 }
\ No newline at end of file
diff --git a/java/160. Intersection of Two Linked Lists.java b/java/160. Intersection of Two Linked Lists.java
index df277c8..81e80ac 100644
--- a/java/160. Intersection of Two Linked Lists.java	
+++ b/java/160. Intersection of Two Linked Lists.java	
@@ -16,23 +16,23 @@ public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
         return compare(headA, a, headB, b);
     }
     public ListNode compare(ListNode headA,int a, ListNode headB,int b) {
-			if (a>b) {
-				return compare(headA.next, a-1, headB, b);
-			}else if (a<b) {
-				return compare(headA, a, headB.next, b-1);
-			}else {
-				if (headA==headB) {
-					return headA;
-				}else {
-					return compare(headA.next, a-1, headB.next, b-1);
-				}
-			}
+            if (a>b) {
+                return compare(headA.next, a-1, headB, b);
+            }else if (a<b) {
+                return compare(headA, a, headB.next, b-1);
+            }else {
+                if (headA==headB) {
+                    return headA;
+                }else {
+                    return compare(headA.next, a-1, headB.next, b-1);
+                }
+            }
     }
     public int Count(ListNode head,int i){
-    	if (head!=null) {
-			i++;
-			i=Count(head.next,i);
-		}
-    	return i;
+        if (head!=null) {
+            i++;
+            i=Count(head.next,i);
+        }
+        return i;
     }
 }
\ No newline at end of file
diff --git a/java/162. Find Peak Element.java b/java/162. Find Peak Element.java
index 53e2127..f1e4c20 100644
--- a/java/162. Find Peak Element.java	
+++ b/java/162. Find Peak Element.java	
@@ -1,19 +1,19 @@
 public class Solution {
     public int findPeakElement(int[] nums) {
-    	if (nums.length==1) {
-			return 0;
-		}
+        if (nums.length==1) {
+            return 0;
+        }
         int s=0;
         int e=nums.length-1;
         int m=(s+e)/2;
         while (e-s>1) {
-        	if (nums[m]>nums[m+1]) {
-				e=m;
-			}else {
-				s=m;
-			}
-        	m=(s+e)/2;
-		}
+            if (nums[m]>nums[m+1]) {
+                e=m;
+            }else {
+                s=m;
+            }
+            m=(s+e)/2;
+        }
         return nums[s]>nums[e]?s:e;
     }
 }
\ No newline at end of file
diff --git a/java/164. Maximum Gap.java b/java/164. Maximum Gap.java
index e0b6c78..80faca5 100644
--- a/java/164. Maximum Gap.java	
+++ b/java/164. Maximum Gap.java	
@@ -1,15 +1,15 @@
 public class Solution {
     public int maximumGap(int[] nums) {
-    	if (nums.length<2) {
-			return 0;
-		}
+        if (nums.length<2) {
+            return 0;
+        }
         Arrays.sort(nums);
         int ans=0;
         for (int i = 1; i < nums.length; i++) {
-			if (ans<(nums[i]-nums[i-1])) {
-				ans=nums[i]-nums[i-1];
-			}
-		}
+            if (ans<(nums[i]-nums[i-1])) {
+                ans=nums[i]-nums[i-1];
+            }
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/165. Compare Version Numbers.java b/java/165. Compare Version Numbers.java
index bca8bec..fffa6ae 100644
--- a/java/165. Compare Version Numbers.java	
+++ b/java/165. Compare Version Numbers.java	
@@ -5,28 +5,28 @@ public int compareVersion(String version1, String version2) {
         int l1=v1.length;
         int l2=v2.length;
         for (int i = 0; i < Math.min(l1, l2); i++) {
-			if (Integer.valueOf(v1[i])<Integer.valueOf(v2[i])) {
-				return -1;
-			}else if (Integer.valueOf(v1[i])>Integer.valueOf(v2[i])) {
-				return 1;
-			}
-		}
+            if (Integer.valueOf(v1[i])<Integer.valueOf(v2[i])) {
+                return -1;
+            }else if (Integer.valueOf(v1[i])>Integer.valueOf(v2[i])) {
+                return 1;
+            }
+        }
         if (l1==l2) {
-			return 0;
-		}else if (l1>l2) {
-			for (int i = l2; i <l1; i++) {
-				if (Integer.parseInt(v1[i])!=0) {
-					return 1;
-				}
-			}
-			return 0;
-		}else {
-			for (int i = l1; i < l2; i++) {
-				if (Integer.parseInt(v2[i])!=0) {
-					return -1;
-				}
-			}
-			return 0;
-		}
+            return 0;
+        }else if (l1>l2) {
+            for (int i = l2; i <l1; i++) {
+                if (Integer.parseInt(v1[i])!=0) {
+                    return 1;
+                }
+            }
+            return 0;
+        }else {
+            for (int i = l1; i < l2; i++) {
+                if (Integer.parseInt(v2[i])!=0) {
+                    return -1;
+                }
+            }
+            return 0;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/166. Fraction to Recurring Decimal.java b/java/166. Fraction to Recurring Decimal.java
index d857981..804cfdb 100644
--- a/java/166. Fraction to Recurring Decimal.java	
+++ b/java/166. Fraction to Recurring Decimal.java	
@@ -1,25 +1,25 @@
 public class Solution {
     public String fractionToDecimal(int numerator, int denominator) {
-    	long n=numerator;
-    	long d=denominator;
-    	if (d==0) {
-			return null;
-		}
-    	if (n==0) {
-			return "0";
-		}
-    	if (n%d==0) {
-    		return String.valueOf(n/d);
-    	}
-    	boolean flag=true;
-    	if (n<0) {
-    		n=0-n;
-    		flag=!flag;
-		}
-		if (d<0) {
-    		d=0-d;
-    		flag=!flag;
-		}
+        long n=numerator;
+        long d=denominator;
+        if (d==0) {
+            return null;
+        }
+        if (n==0) {
+            return "0";
+        }
+        if (n%d==0) {
+            return String.valueOf(n/d);
+        }
+        boolean flag=true;
+        if (n<0) {
+            n=0-n;
+            flag=!flag;
+        }
+        if (d<0) {
+            d=0-d;
+            flag=!flag;
+        }
         Map<Long, Integer> map=new HashMap<Long, Integer>();
         StringBuffer sb=new StringBuffer();
         sb.append(String.valueOf(n/d)).append(".");
@@ -27,21 +27,21 @@ public String fractionToDecimal(int numerator, int denominator) {
         int i=1;
         map.put(n, i);
         while (true) {
-        	n*=10;
-        	sb.append(String.valueOf(n/d));
-        	n%=d;
-        	if (n==0) {
-				return flag?sb.toString():"-"+sb.toString();
-			}
-        	i++;
-        	if (map.get(n)==null) {
-        		map.put(n, i);
-			}else {
-				String str=sb.toString();
-				String circle=str.substring(str.length()-(i-Integer.valueOf(map.get(n))), str.length());
-				String answer=str.substring(0,str.length()-(i-Integer.valueOf(map.get(n))))+"("+circle+")";
-				return flag?answer:"-"+answer;
-			}
-		}
+            n*=10;
+            sb.append(String.valueOf(n/d));
+            n%=d;
+            if (n==0) {
+                return flag?sb.toString():"-"+sb.toString();
+            }
+            i++;
+            if (map.get(n)==null) {
+                map.put(n, i);
+            }else {
+                String str=sb.toString();
+                String circle=str.substring(str.length()-(i-Integer.valueOf(map.get(n))), str.length());
+                String answer=str.substring(0,str.length()-(i-Integer.valueOf(map.get(n))))+"("+circle+")";
+                return flag?answer:"-"+answer;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/168. Excel Sheet Column Title.java b/java/168. Excel Sheet Column Title.java
index b9c1051..051c841 100644
--- a/java/168. Excel Sheet Column Title.java	
+++ b/java/168. Excel Sheet Column Title.java	
@@ -1,48 +1,48 @@
 public class Solution {
     public String convertToTitle(int n) {
-    	List<Integer> list=new ArrayList<Integer>();
+        List<Integer> list=new ArrayList<Integer>();
         while (n!=0) {
-			list.add(n%26);
-			n/=26;
-		}
+            list.add(n%26);
+            n/=26;
+        }
         boolean flag=false;
         List<Integer> l=new ArrayList<Integer>();
         for (int i = 0; i <list.size(); i++) {
-        	int k=list.get(i);
-			if(flag){
-				if (k>1) {
-					l.add(k-1);
-					flag=false;
-				}else if(k==1){
-					l.add(26);
-					flag=true;
-				}else {
-					l.add(25);
-					flag=true;
-				}
-			}else {
-				if (k!=0) {
-					l.add(k);
-					flag=false;
-				}
-				else {
-					l.add(26);
-					flag=true;
-				}
-			}
-		}
+            int k=list.get(i);
+            if(flag){
+                if (k>1) {
+                    l.add(k-1);
+                    flag=false;
+                }else if(k==1){
+                    l.add(26);
+                    flag=true;
+                }else {
+                    l.add(25);
+                    flag=true;
+                }
+            }else {
+                if (k!=0) {
+                    l.add(k);
+                    flag=false;
+                }
+                else {
+                    l.add(26);
+                    flag=true;
+                }
+            }
+        }
         int m=l.size();
         if (flag) {
-			m--;
-		}
+            m--;
+        }
         String answer="";
          for (int i = m-1; i >=0; i--) {
-			int k=l.get(i);
-			k+=64;
-			char c=(char) k;
-			String s=String.valueOf(c);
-			answer+=s;
-		}
-    	return answer;
+            int k=l.get(i);
+            k+=64;
+            char c=(char) k;
+            String s=String.valueOf(c);
+            answer+=s;
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/169. Majority Element.java b/java/169. Majority Element.java
index edb843d..fe8e6da 100644
--- a/java/169. Majority Element.java	
+++ b/java/169. Majority Element.java	
@@ -1,6 +1,6 @@
 public class Solution {
     public int majorityElement(int[] nums) {
-    	Arrays.sort(nums);
-    	return nums[nums.length/2];
+        Arrays.sort(nums);
+        return nums[nums.length/2];
     }
 }
\ No newline at end of file
diff --git a/java/171. Excel Sheet Column Number.java b/java/171. Excel Sheet Column Number.java
index fcb3e16..f23c3e0 100644
--- a/java/171. Excel Sheet Column Number.java	
+++ b/java/171. Excel Sheet Column Number.java	
@@ -1,32 +1,32 @@
 public class Solution {
     public int titleToNumber(String s) {
-    	int[] a=new int[s.length()];
-    	boolean flag=false;
+        int[] a=new int[s.length()];
+        boolean flag=false;
         for (int i = s.length()-1; i>=0; i--) {
-			String k=s.substring(i,i+1);
-			int ik= (int)(k.toCharArray()[0])-64;
-			if (flag) {
-				ik++;
-			}
-			if (ik!=26) {
-				a[s.length()-1-i]=ik;
-				flag=false;
-			}else {
-				a[s.length()-1-i]=0;
-				flag=true;
-			}
-		}
+            String k=s.substring(i,i+1);
+            int ik= (int)(k.toCharArray()[0])-64;
+            if (flag) {
+                ik++;
+            }
+            if (ik!=26) {
+                a[s.length()-1-i]=ik;
+                flag=false;
+            }else {
+                a[s.length()-1-i]=0;
+                flag=true;
+            }
+        }
         int p=1;
         int sum=0;
         for (int i = 0; i < a.length; i++) {
-			if (i!=0) {
-				p*=26;
-			}
-			sum+=a[i]*p;
-		}
-		if (flag) {
-			return sum+=p*26;
-		}
-    	return sum;
+            if (i!=0) {
+                p*=26;
+            }
+            sum+=a[i]*p;
+        }
+        if (flag) {
+            return sum+=p*26;
+        }
+        return sum;
     }
 }
\ No newline at end of file
diff --git a/java/172. Factorial Trailing Zeroes.java b/java/172. Factorial Trailing Zeroes.java
index ad0e0e5..131dd7d 100644
--- a/java/172. Factorial Trailing Zeroes.java	
+++ b/java/172. Factorial Trailing Zeroes.java	
@@ -1,10 +1,10 @@
 public class Solution {
     public int trailingZeroes(int n) {
-    	int sum=0;
-    	while (n!=0) {
-    		n/=5;
-			sum+=n;
-		}
-    	return sum;
+        int sum=0;
+        while (n!=0) {
+            n/=5;
+            sum+=n;
+        }
+        return sum;
     }
 }
\ No newline at end of file
diff --git a/java/179. Largest Number.java b/java/179. Largest Number.java
index a8ae40b..cf7993c 100644
--- a/java/179. Largest Number.java	
+++ b/java/179. Largest Number.java	
@@ -1,39 +1,39 @@
 public class Solution {
-	public String largestNumber(int[] nums) {
-		if (nums.length == 1) {
-			return String.valueOf(nums[0]);
-		}
-		int temp = 0;
-		for (int i = nums.length - 1; i > 0; i--) {
-			for (int j = 0; j < i; ++j) {
-				if (new Solution().compare(nums[j], nums[j + 1])) {
-					temp = nums[j];
-					nums[j] = nums[j + 1];
-					nums[j + 1] = temp;
-				}
-			}
-		}
-		StringBuffer sb = new StringBuffer();
-		if (nums[nums.length - 1] == 0) {
-			return "0";
-		}
-		for (int i = nums.length - 1; i >= 0; i--) {
-			sb.append(String.valueOf(nums[i]));
-		}
-		return sb.toString();
-	}
+    public String largestNumber(int[] nums) {
+        if (nums.length == 1) {
+            return String.valueOf(nums[0]);
+        }
+        int temp = 0;
+        for (int i = nums.length - 1; i > 0; i--) {
+            for (int j = 0; j < i; ++j) {
+                if (new Solution().compare(nums[j], nums[j + 1])) {
+                    temp = nums[j];
+                    nums[j] = nums[j + 1];
+                    nums[j + 1] = temp;
+                }
+            }
+        }
+        StringBuffer sb = new StringBuffer();
+        if (nums[nums.length - 1] == 0) {
+            return "0";
+        }
+        for (int i = nums.length - 1; i >= 0; i--) {
+            sb.append(String.valueOf(nums[i]));
+        }
+        return sb.toString();
+    }
 
-	public boolean compare(int a, int b) {
-		char[] ca=(String.valueOf(a)+String.valueOf(b)).toCharArray();
-		char[] cb=(String.valueOf(b)+String.valueOf(a)).toCharArray();
-		for (int i = 0; i < ca.length; i++) {
-			if (ca[i]>cb[i]) {
-				return true;
-			}
-			if (ca[i]<cb[i]) {
-				return false;
-			}
-		}
-		return false;
-	}
+    public boolean compare(int a, int b) {
+        char[] ca=(String.valueOf(a)+String.valueOf(b)).toCharArray();
+        char[] cb=(String.valueOf(b)+String.valueOf(a)).toCharArray();
+        for (int i = 0; i < ca.length; i++) {
+            if (ca[i]>cb[i]) {
+                return true;
+            }
+            if (ca[i]<cb[i]) {
+                return false;
+            }
+        }
+        return false;
+    }
 }
\ No newline at end of file
diff --git a/java/187. Repeated DNA Sequences.java b/java/187. Repeated DNA Sequences.java
index 09df2ec..00b5554 100644
--- a/java/187. Repeated DNA Sequences.java	
+++ b/java/187. Repeated DNA Sequences.java	
@@ -4,14 +4,14 @@ public List<String> findRepeatedDnaSequences(String s) {
         Map<String,Integer> trash=new HashMap<String, Integer>();
         List<String> ans=new ArrayList<String>();
         for (int i = 0; i < s.length()-9; i++) {
-        	String k=s.substring(i,i+10);
-        	if (map.get(k)==null) {
-				map.put(k, 1);
-			}else if(trash.get(k)==null){
-				trash.put(k, 1);
-				ans.add(k);
-			}
-		}
-    	return ans;
+            String k=s.substring(i,i+10);
+            if (map.get(k)==null) {
+                map.put(k, 1);
+            }else if(trash.get(k)==null){
+                trash.put(k, 1);
+                ans.add(k);
+            }
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/189. Rotate Array.java b/java/189. Rotate Array.java
index 200ee84..e3f976a 100644
--- a/java/189. Rotate Array.java	
+++ b/java/189. Rotate Array.java	
@@ -1,15 +1,15 @@
 public class Solution {
     public void rotate(int[] nums, int k) {
-    	k=k%nums.length;
+        k=k%nums.length;
         List<Integer> list=new ArrayList<Integer>();
         for (int i = nums.length-k; i < nums.length; i++) {
-			list.add(nums[i]);
-		}
+            list.add(nums[i]);
+        }
         for (int i = nums.length-1; i >=k; i--) {
-			nums[i]=nums[i-k];
-		}
+            nums[i]=nums[i-k];
+        }
         for (int i = 0; i < k; i++) {
-			nums[i]=list.get(i);
-		}
+            nums[i]=list.get(i);
+        }
     }
 }
\ No newline at end of file
diff --git a/java/191. Number of 1 Bits.java b/java/191. Number of 1 Bits.java
index 0f79941..1825ea5 100644
--- a/java/191. Number of 1 Bits.java	
+++ b/java/191. Number of 1 Bits.java	
@@ -3,9 +3,9 @@ public class Solution {
     public int hammingWeight(int n) {
         int ans=0;
         while (n!=0) {
-			ans+=n&1;
-			n>>>=1;
-		}
+            ans+=n&1;
+            n>>>=1;
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/198. House Robber.java b/java/198. House Robber.java
index bf3653b..c91212d 100644
--- a/java/198. House Robber.java	
+++ b/java/198. House Robber.java	
@@ -1,15 +1,15 @@
 public class Solution {
     public int rob(int[] nums) {
         int n=nums.length;
-    	if (n==0) {
-			return 0;
-		}
+        if (n==0) {
+            return 0;
+        }
         int[] ans=new int[n+1];
         ans[0]=0;
         ans[1]=nums[0];
         for (int i = 2; i < n+1; i++) {
-			ans[i]=Math.max(nums[i-1]+ans[i-2], ans[i-1]);
-		}
-    	return ans[n];
+            ans[i]=Math.max(nums[i-1]+ans[i-2], ans[i-1]);
+        }
+        return ans[n];
     }
 }
\ No newline at end of file
diff --git a/java/199. Binary Tree Right Side View.java b/java/199. Binary Tree Right Side View.java
index aa294be..0457586 100644
--- a/java/199. Binary Tree Right Side View.java	
+++ b/java/199. Binary Tree Right Side View.java	
@@ -9,28 +9,28 @@
  */
 public class Solution {
     public List<Integer> rightSideView(TreeNode root) {
-    	List<Integer> answer=new ArrayList<Integer>();
-    	if (root==null) {
-    		return answer;
-    	}
-    	List<TreeNode> list=new ArrayList<TreeNode>();
-    	list.add(root);
-    	int k=list.size();
-    	while (k>0) {
-			answer.add(list.get(list.size()-1).val);
-			for (int i = 0; i < k; i++) {
-				if (list.get(i).left!=null) {
-					list.add(list.get(i).left);
-				}
-				if (list.get(i).right!=null) {
-					list.add(list.get(i).right);
-				}
-				list.remove(i);
-				i--;
-				k--;
-			}
-			k=list.size();
-		}
-    	return answer;
+        List<Integer> answer=new ArrayList<Integer>();
+        if (root==null) {
+            return answer;
+        }
+        List<TreeNode> list=new ArrayList<TreeNode>();
+        list.add(root);
+        int k=list.size();
+        while (k>0) {
+            answer.add(list.get(list.size()-1).val);
+            for (int i = 0; i < k; i++) {
+                if (list.get(i).left!=null) {
+                    list.add(list.get(i).left);
+                }
+                if (list.get(i).right!=null) {
+                    list.add(list.get(i).right);
+                }
+                list.remove(i);
+                i--;
+                k--;
+            }
+            k=list.size();
+        }
+        return answer;
     }
 }
\ No newline at end of file
diff --git a/java/200. Number of Islands.java b/java/200. Number of Islands.java
index b543fdc..14dd7c9 100644
--- a/java/200. Number of Islands.java	
+++ b/java/200. Number of Islands.java	
@@ -1,41 +1,41 @@
 public class Solution {
     public int numIslands(char[][] grid) {
-		int il = 0;
-		Map<String, String> map = new HashMap<String, String>();
-		for (int i = 0; i < grid.length; i++) {
-			for (int j = 0; j < grid[i].length; j++) {
-				if (map.get("(" + i + "," + j + ")") == null) {
-					if (grid[i][j] == &#39;1&#39;) {
-						il++;
-						map = new Solution().ss(map, i, j, grid);
-					}
-				}
-			}
-		}
-		return il;
+        int il = 0;
+        Map<String, String> map = new HashMap<String, String>();
+        for (int i = 0; i < grid.length; i++) {
+            for (int j = 0; j < grid[i].length; j++) {
+                if (map.get("(" + i + "," + j + ")") == null) {
+                    if (grid[i][j] == &#39;1&#39;) {
+                        il++;
+                        map = new Solution().ss(map, i, j, grid);
+                    }
+                }
+            }
+        }
+        return il;
     }
    public Map<String,String> ss(Map<String,String> map,int i,int j,char[][] grid){
-		if (map.get("(" + i + "," + j + ")") == null && grid[i][j] == &#39;1&#39;) {
-			int LI = grid.length;
-			int LJ = grid[i].length;
-			map.put("(" + i + "," + j + ")", "1");
-			if (i > 0) {
-				// 上边检测
-				map = ss(map, i - 1, j, grid);
-			}
-			if (i < LI - 1) {
-				// 下边检测
-				map = ss(map, i + 1, j, grid);
-			}
-			if (j > 0) {
-				// 左边检测
-				map = ss(map, i, j - 1, grid);
-			}
-			if (j < LJ - 1) {
-				// 右边检测
-				map = ss(map, i, j + 1, grid);
-			}
-		}
-		return map;
-	}
+        if (map.get("(" + i + "," + j + ")") == null && grid[i][j] == &#39;1&#39;) {
+            int LI = grid.length;
+            int LJ = grid[i].length;
+            map.put("(" + i + "," + j + ")", "1");
+            if (i > 0) {
+                // 上边检测
+                map = ss(map, i - 1, j, grid);
+            }
+            if (i < LI - 1) {
+                // 下边检测
+                map = ss(map, i + 1, j, grid);
+            }
+            if (j > 0) {
+                // 左边检测
+                map = ss(map, i, j - 1, grid);
+            }
+            if (j < LJ - 1) {
+                // 右边检测
+                map = ss(map, i, j + 1, grid);
+            }
+        }
+        return map;
+    }
 }
\ No newline at end of file
diff --git a/java/201. Bitwise AND of Numbers Range.java b/java/201. Bitwise AND of Numbers Range.java
index 3122357..0d98873 100644
--- a/java/201. Bitwise AND of Numbers Range.java	
+++ b/java/201. Bitwise AND of Numbers Range.java	
@@ -1,7 +1,7 @@
 public class Solution {
     public int rangeBitwiseAnd(int m, int n) {
         if(m==n){
-        	return n;
+            return n;
         }
         int s=(int) Math.pow(2,(int) (Math.log(m^n)/Math.log(2))+1);
         return ((m&n)/s)*s;
diff --git a/java/202. Happy Number.java b/java/202. Happy Number.java
index fa01f58..8147634 100644
--- a/java/202. Happy Number.java	
+++ b/java/202. Happy Number.java	
@@ -5,21 +5,21 @@ public boolean isHappy(int n) {
         map.put(s, "存在");
         int sum=0;
         while (true) {
-			for (int i = 0; i < s.length(); i++) {
-				int k=Integer.parseInt(s.substring(i,i+1));
-				sum+=k*k;
-			}
-			if (sum==1) {
-				return true;
-			}
-			if (map.get(String.valueOf(sum))!=null) {
-				return false;
-			}else {
-				s=String.valueOf(sum);
-				map.put(s, "存在");
-				sum=0;
-			}
-			
-		}
+            for (int i = 0; i < s.length(); i++) {
+                int k=Integer.parseInt(s.substring(i,i+1));
+                sum+=k*k;
+            }
+            if (sum==1) {
+                return true;
+            }
+            if (map.get(String.valueOf(sum))!=null) {
+                return false;
+            }else {
+                s=String.valueOf(sum);
+                map.put(s, "存在");
+                sum=0;
+            }
+            
+        }
     }
 }
\ No newline at end of file
diff --git a/java/203. Remove Linked List Elements.java b/java/203. Remove Linked List Elements.java
index 83d0862..532bd5b 100644
--- a/java/203. Remove Linked List Elements.java	
+++ b/java/203. Remove Linked List Elements.java	
@@ -8,24 +8,24 @@
  */
 public class Solution {
     public ListNode removeElements(ListNode head,int val) {
-    	List<ListNode> list=zuhe(head, new ArrayList<ListNode>(),val);
-    	if (list.size()==0) {
-    		return null;
-    	}
-    	for (int i = 0; i < list.size()-1; i++) {
-			list.get(i).next=list.get(i+1);
-		}
-    	list.get(list.size()-1).next=null;
-    	return list.get(0);
+        List<ListNode> list=zuhe(head, new ArrayList<ListNode>(),val);
+        if (list.size()==0) {
+            return null;
+        }
+        for (int i = 0; i < list.size()-1; i++) {
+            list.get(i).next=list.get(i+1);
+        }
+        list.get(list.size()-1).next=null;
+        return list.get(0);
     }
 
     public List<ListNode> zuhe(ListNode head,List<ListNode> list, int val){
-    	if (head!=null) {
-    		if (head.val!=val) {
-    			list.add(head);
-			}
-			list=zuhe(head.next,list,val);
-		}
-    	return list;
+        if (head!=null) {
+            if (head.val!=val) {
+                list.add(head);
+            }
+            list=zuhe(head.next,list,val);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/204. Count Primes.java b/java/204. Count Primes.java
index b57e72c..845f46d 100644
--- a/java/204. Count Primes.java	
+++ b/java/204. Count Primes.java	
@@ -1,15 +1,15 @@
 public class Solution {
     public int countPrimes(int n) {
-    	boolean[] flag=new boolean[n];
-    	int ans=0;
-    	for (int i = 2; i < flag.length; i++) {
-			if (!flag[i]) {
-				ans++;
-				for (int j = i; j < flag.length; j+=i) {
-					flag[j]=true;
-				}
-			}
-		}
-    	return ans;
+        boolean[] flag=new boolean[n];
+        int ans=0;
+        for (int i = 2; i < flag.length; i++) {
+            if (!flag[i]) {
+                ans++;
+                for (int j = i; j < flag.length; j+=i) {
+                    flag[j]=true;
+                }
+            }
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/205. Isomorphic Strings.java b/java/205. Isomorphic Strings.java
index a913a60..958ce24 100644
--- a/java/205. Isomorphic Strings.java	
+++ b/java/205. Isomorphic Strings.java	
@@ -1,25 +1,25 @@
 public class Solution {
     public boolean isIsomorphic(String s, String t) {
         if (s.length()!=t.length()) {
-			return false;
-		}
+            return false;
+        }
         Map<String,Integer> sMap=new HashMap<String, Integer>();
         Map<String,Integer> tMap=new HashMap<String, Integer>();
         for (int i = 0; i < s.length(); i++) {
-			String sk=s.substring(i,i+1);
-			String tk=t.substring(i,i+1);
-			if ((sMap.get(sk)==null)!=((tMap.get(tk)==null))) {
-				return false;
-			}else if (sMap.get(sk)==null) {
-				sMap.put(sk, i);
-				tMap.put(tk, i);
-			}else if(!sMap.get(sk).equals(tMap.get(tk))){
-				return false;
-			}else {
-				sMap.put(sk, i);
-				tMap.put(tk, i);
-			}
-		}
+            String sk=s.substring(i,i+1);
+            String tk=t.substring(i,i+1);
+            if ((sMap.get(sk)==null)!=((tMap.get(tk)==null))) {
+                return false;
+            }else if (sMap.get(sk)==null) {
+                sMap.put(sk, i);
+                tMap.put(tk, i);
+            }else if(!sMap.get(sk).equals(tMap.get(tk))){
+                return false;
+            }else {
+                sMap.put(sk, i);
+                tMap.put(tk, i);
+            }
+        }
         return true;
     }
 }
\ No newline at end of file
diff --git a/java/206. Reverse Linked List.java b/java/206. Reverse Linked List.java
index bded3af..b102816 100644
--- a/java/206. Reverse Linked List.java	
+++ b/java/206. Reverse Linked List.java	
@@ -9,21 +9,21 @@
 public class Solution {
     public ListNode reverseList(ListNode head) {
         if (head==null) {
-			return head;
-		}
-    	List<ListNode> list=zuhe(head, new ArrayList<ListNode>());
+            return head;
+        }
+        List<ListNode> list=zuhe(head, new ArrayList<ListNode>());
         for (int i = list.size()-1; i >0; i--) {
-			list.get(i).next=list.get(i-1);
-		}
+            list.get(i).next=list.get(i-1);
+        }
         list.get(0).next=null;
         return list.get(list.size()-1);
     }
     
     public List<ListNode> zuhe(ListNode head,List<ListNode> list){
-    	if (head!=null) {
-			list.add(head);
-			list=zuhe(head.next,list);
-		}
-    	return list;
+        if (head!=null) {
+            list.add(head);
+            list=zuhe(head.next,list);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/208. Implement Trie (Prefix Tree).java b/java/208. Implement Trie (Prefix Tree).java
index a60cffb..a47caa3 100644
--- a/java/208. Implement Trie (Prefix Tree).java	
+++ b/java/208. Implement Trie (Prefix Tree).java	
@@ -18,7 +18,7 @@ public Trie() {
     // Inserts a word into the trie.
     public void insert(String word) {
         if(!search(word)){
-        	TrieNode tt=root;
+            TrieNode tt=root;
             char[] ac=word.toCharArray();
             for(int i=0;i<ac.length;i++){
                 Map<Character,TrieNode> sons=root.sons;
@@ -42,7 +42,7 @@ public void insert(String word) {
 
     // Returns if the word is in the trie.
     public boolean search(String word) {
-    	TrieNode tt=root;
+        TrieNode tt=root;
         char[] ac=word.toCharArray();
         for(int i=0;i<ac.length;i++){
             Map<Character,TrieNode> sons=root.sons;
@@ -60,7 +60,7 @@ public boolean search(String word) {
     // Returns if there is any word in the trie
     // that starts with the given prefix.
     public boolean startsWith(String prefix) {
-    	TrieNode tt=root;
+        TrieNode tt=root;
         char[] ac=prefix.toCharArray();
         for(int i=0;i<ac.length;i++){
             Map<Character,TrieNode> sons=root.sons;
diff --git a/java/212. Word Search II.java b/java/212. Word Search II.java
index c0d4312..7001f64 100644
--- a/java/212. Word Search II.java	
+++ b/java/212. Word Search II.java	
@@ -1,17 +1,17 @@
 public class Solution {
-	Map<Character, Map<Character, Integer>> map=new HashMap<Character, Map<Character,Integer>>();
-	Map<String,Integer> finish=new HashMap<String, Integer>();
+    Map<Character, Map<Character, Integer>> map=new HashMap<Character, Map<Character,Integer>>();
+    Map<String,Integer> finish=new HashMap<String, Integer>();
     public List<String> findWords(char[][] board, String[] words) {
-    	List<String> ans=new ArrayList<String>();
-    	init(board);
-    	for (int i = 0; i < words.length; i++) {
-    		if (finish.get(words[i])==null&&pre(words[i])&&exist(board, words[i])) {
-    			ans.add(words[i]);
-			}
-    		//验证过的字符串不再次验证
-    		finish.put(words[i], 1);
-		}
-    	return ans;
+        List<String> ans=new ArrayList<String>();
+        init(board);
+        for (int i = 0; i < words.length; i++) {
+            if (finish.get(words[i])==null&&pre(words[i])&&exist(board, words[i])) {
+                ans.add(words[i]);
+            }
+            //验证过的字符串不再次验证
+            finish.put(words[i], 1);
+        }
+        return ans;
     }
     /**
      * 粗略判断，判断字符串中的每个字符是否出现在表格上以及下一个字符是否在该字符周围可以找到
@@ -21,44 +21,44 @@ public List<String> findWords(char[][] board, String[] words) {
      * @return
      */
     public boolean pre(String word){
-    	char[] c=word.toCharArray();
-    	for (int i = 0; i < c.length-1; i++) {
-			char b=c[i];
-			char e=c[i+1];
-			if (map.get(b)==null||map.get(b).get(e)==null) {
-				return false;
-			}
-		}
-    	return true;
+        char[] c=word.toCharArray();
+        for (int i = 0; i < c.length-1; i++) {
+            char b=c[i];
+            char e=c[i+1];
+            if (map.get(b)==null||map.get(b).get(e)==null) {
+                return false;
+            }
+        }
+        return true;
     }
     /**
      * 预处理，先把每个字符周围的值写进map
      * @param board
      */
     public void init(char[][] board){
-    	int iL=board.length;
-    	int jL=board[0].length;
-    	for (int i = 0; i < iL; i++) {
-			for (int j = 0; j < jL; j++) {
-				Map<Character, Integer> m=map.get(board[i][j]);
-				if (m==null) {
-					m=new HashMap<Character, Integer>();
-				}
-				if (i-1>=0) {
-					m.put(board[i-1][j], 1);
-				}
-				if (i+1<iL) {
-					m.put(board[i+1][j], 1);
-				}
-				if (j-1>=0) {
-					m.put(board[i][j-1], 1);
-				}
-				if (j+1<jL) {
-					m.put(board[i][j+1], 1);
-				}
-				map.put(board[i][j], m);
-			}
-		}
+        int iL=board.length;
+        int jL=board[0].length;
+        for (int i = 0; i < iL; i++) {
+            for (int j = 0; j < jL; j++) {
+                Map<Character, Integer> m=map.get(board[i][j]);
+                if (m==null) {
+                    m=new HashMap<Character, Integer>();
+                }
+                if (i-1>=0) {
+                    m.put(board[i-1][j], 1);
+                }
+                if (i+1<iL) {
+                    m.put(board[i+1][j], 1);
+                }
+                if (j-1>=0) {
+                    m.put(board[i][j-1], 1);
+                }
+                if (j+1<jL) {
+                    m.put(board[i][j+1], 1);
+                }
+                map.put(board[i][j], m);
+            }
+        }
     }
     public boolean exist(char[][] board, String word) { 
         if (word==null||word.length()==0||board==null||board.length==0) {  
@@ -80,15 +80,15 @@ public boolean exist(char[][] board, String word) {
     }
     /**
      * 各参数含义
-     * @param board	参照表格
-     * @param ch	测试的字符串转成字符数组
-     * @param level	测试数组的下标
-     * @param x		探测表格的横坐标
-     * @param y		探测表格的纵坐标
+     * @param board    参照表格
+     * @param ch    测试的字符串转成字符数组
+     * @param level    测试数组的下标
+     * @param x        探测表格的横坐标
+     * @param y        探测表格的纵坐标
      * @param length数组的长度
-     * @param m		表格的横长
-     * @param n		表格的纵长
-     * @param flag	标记表格该位置的字符是否被使用过，true表示使用过，false表示未使用过
+     * @param m        表格的横长
+     * @param n        表格的纵长
+     * @param flag    标记表格该位置的字符是否被使用过，true表示使用过，false表示未使用过
      * @return
      */
     public boolean f(char[][] board,char[] ch,int level,int x,int y,int length,int m,int n,boolean[][] flag){  
diff --git a/java/213. House Robber II.java b/java/213. House Robber II.java
index b11134e..ba6b150 100644
--- a/java/213. House Robber II.java	
+++ b/java/213. House Robber II.java	
@@ -1,23 +1,23 @@
 public class Solution {
     public int rob(int[] nums) {
         if (nums.length==0) {
-			return 0;
-		}
+            return 0;
+        }
         if (nums.length==1) {
-			return nums[0];
-		}
+            return nums[0];
+        }
         int[] dp=new int[nums.length];
         //第一家到倒数第二家
         dp[0] = nums[0];
         for (int i = 1; i < nums.length-1; i++) {
-			dp[i]=Math.max(dp[i-1], (i==1?0:dp[i-2])+nums[i]);
-		}
+            dp[i]=Math.max(dp[i-1], (i==1?0:dp[i-2])+nums[i]);
+        }
         int res=dp[nums.length-2];
         //第二家到倒数第一家
         dp[1] = nums[1];
         for (int i = 2; i < nums.length; i++) {
-			dp[i]=Math.max(dp[i-1], (i==2?0:dp[i-2])+nums[i]);
-		}
+            dp[i]=Math.max(dp[i-1], (i==2?0:dp[i-2])+nums[i]);
+        }
         return Math.max(res, dp[dp.length-1]);
     }
 }
\ No newline at end of file
diff --git a/java/216. Combination Sum III.java b/java/216. Combination Sum III.java
index d023feb..9fbbee3 100644
--- a/java/216. Combination Sum III.java	
+++ b/java/216. Combination Sum III.java	
@@ -1,39 +1,39 @@
 public class Solution {
     public List<List<Integer>> combinationSum3(int k, int n) {
-		List<List<Integer>> answerList = new ArrayList<List<Integer>>();
-		for (int i = 1; i < 10; i++) {
-			List<Integer> list = new ArrayList<Integer>();
-			list.add(i);
-			answerList.add(list);
-		}
-		for (int i = 0; i < answerList.size(); i++) {
-			List<Integer> list = answerList.get(i);
-			int length=list.size();
-			int value=n-sum(list);
-			if (length== k && value==0) {
-				continue;
-			} else {
-				if (value>0) {
-					for (int j = list.get(length- 1) + 1; j <=(value>9?9:value); j++) {
-						if (length<k) {
-							List<Integer> newList = new ArrayList<Integer>();
-							newList.addAll(list);
-							newList.add(j);
-							answerList.add(newList);
-						}
-					}
-				}
-				answerList.remove(i);
-				i--;
-			}
-		}
-		return answerList;
-	}
+        List<List<Integer>> answerList = new ArrayList<List<Integer>>();
+        for (int i = 1; i < 10; i++) {
+            List<Integer> list = new ArrayList<Integer>();
+            list.add(i);
+            answerList.add(list);
+        }
+        for (int i = 0; i < answerList.size(); i++) {
+            List<Integer> list = answerList.get(i);
+            int length=list.size();
+            int value=n-sum(list);
+            if (length== k && value==0) {
+                continue;
+            } else {
+                if (value>0) {
+                    for (int j = list.get(length- 1) + 1; j <=(value>9?9:value); j++) {
+                        if (length<k) {
+                            List<Integer> newList = new ArrayList<Integer>();
+                            newList.addAll(list);
+                            newList.add(j);
+                            answerList.add(newList);
+                        }
+                    }
+                }
+                answerList.remove(i);
+                i--;
+            }
+        }
+        return answerList;
+    }
     public int sum(List<Integer> list){
-    	int sum=0; 
-    	for (int i = 0; i < list.size(); i++) {
-			sum+=list.get(i);
-		}
-    	return sum;
+        int sum=0; 
+        for (int i = 0; i < list.size(); i++) {
+            sum+=list.get(i);
+        }
+        return sum;
     }
 }
\ No newline at end of file
diff --git a/java/219. Contains Duplicate II.java b/java/219. Contains Duplicate II.java
index 8e8515b..bdb1a1d 100644
--- a/java/219. Contains Duplicate II.java	
+++ b/java/219. Contains Duplicate II.java	
@@ -3,17 +3,17 @@ public boolean containsNearbyDuplicate(int[] nums, int k) {
         if(nums.length<=1){
             return false;
         }
-		Map<Integer, String> map = new HashMap<Integer, String>();
-		for (int i = 0; i < nums.length; i++) {
-			if (map.get(nums[i]) == null) {
-				map.put(nums[i], "");
-				if (i >= k) {
-					map.remove(nums[i - k]);
-				}
-			} else {
-				return true;
-			}
-		}
-	return false;
+        Map<Integer, String> map = new HashMap<Integer, String>();
+        for (int i = 0; i < nums.length; i++) {
+            if (map.get(nums[i]) == null) {
+                map.put(nums[i], "");
+                if (i >= k) {
+                    map.remove(nums[i - k]);
+                }
+            } else {
+                return true;
+            }
+        }
+    return false;
     }
 }
\ No newline at end of file
diff --git a/java/221. Maximal Square.java b/java/221. Maximal Square.java
index 0144a48..7a9e718 100644
--- a/java/221. Maximal Square.java	
+++ b/java/221. Maximal Square.java	
@@ -1,32 +1,32 @@
 public class Solution {
     public int maximalSquare(char[][] matrix) {
-    	int cross=matrix.length;
-    	if (cross==0) {
-			return 0;
-		}
-    	int vertical=matrix[0].length;
-    	int max=0;
+        int cross=matrix.length;
+        if (cross==0) {
+            return 0;
+        }
+        int vertical=matrix[0].length;
+        int max=0;
         int[][] size=new int[cross][vertical];
         for (int i = 0; i < cross; i++) {
-        	size[i][0]=matrix[i][0]==&#39;1&#39;?1:0;
-        	if (size[i][0]>max) {
-        		max=size[i][0];
-			}
-		}
+            size[i][0]=matrix[i][0]==&#39;1&#39;?1:0;
+            if (size[i][0]>max) {
+                max=size[i][0];
+            }
+        }
         for (int i = 0; i < vertical; i++) {
-        	size[0][i]=matrix[0][i]==&#39;1&#39;?1:0;
-        	if (size[0][i]>max) {
-        		max=size[0][i];
-			}
-		}
+            size[0][i]=matrix[0][i]==&#39;1&#39;?1:0;
+            if (size[0][i]>max) {
+                max=size[0][i];
+            }
+        }
         for (int i = 1; i < cross; i++) {
-			for (int j = 1; j < vertical; j++) {
-				size[i][j]=matrix[i][j]==&#39;1&#39;?Math.min(Math.min(size[i-1][j], size[i][j-1]), size[i-1][j-1])+1:0;
-				if (size[i][j]>max) {
-					max=size[i][j];
-				}
-			}
-		} 
+            for (int j = 1; j < vertical; j++) {
+                size[i][j]=matrix[i][j]==&#39;1&#39;?Math.min(Math.min(size[i-1][j], size[i][j-1]), size[i-1][j-1])+1:0;
+                if (size[i][j]>max) {
+                    max=size[i][j];
+                }
+            }
+        } 
         return max*max;
     }
 }
\ No newline at end of file
diff --git a/java/222. Count Complete Tree Nodes.java b/java/222. Count Complete Tree Nodes.java
index 5d66e11..ff70cc2 100644
--- a/java/222. Count Complete Tree Nodes.java	
+++ b/java/222. Count Complete Tree Nodes.java	
@@ -9,30 +9,30 @@
  */
 public class Solution {
     public int countNodes(TreeNode root) {
-    	if (root==null) {
-			return 0;
-		}
+        if (root==null) {
+            return 0;
+        }
         int l=getLeft(root);
         int r=getRight(root);
         if (l==r) {
-			return (2<<(l-1)) - 1;  
-		}
+            return (2<<(l-1)) - 1;  
+        }
         return 1+countNodes(root.left) + countNodes(root.right) ;  
     }
     public int getLeft(TreeNode root){
-    	int h=0;
-    	while(root!=null){
-    	    h++;
-    	    root=root.left;
-    	}
-    	return h;
+        int h=0;
+        while(root!=null){
+            h++;
+            root=root.left;
+        }
+        return h;
     }
     public int getRight(TreeNode root){
         int h=0;
-    	while(root!=null){
-    	    h++;
-    	    root=root.right;
-    	}
-    	return h;
+        while(root!=null){
+            h++;
+            root=root.right;
+        }
+        return h;
     }
 }
\ No newline at end of file
diff --git a/java/226. Invert Binary Tree.java b/java/226. Invert Binary Tree.java
index 300eeda..a4d14bc 100644
--- a/java/226. Invert Binary Tree.java	
+++ b/java/226. Invert Binary Tree.java	
@@ -9,13 +9,13 @@
  */
 public class Solution {
     public TreeNode invertTree(TreeNode root) {
-		if (root != null) {
-			TreeNode node = root.left;
-			root.left = root.right;
-			root.right = node;
-			root.left = invertTree(root.left);
-			root.right = invertTree(root.right);
-		}
+        if (root != null) {
+            TreeNode node = root.left;
+            root.left = root.right;
+            root.right = node;
+            root.left = invertTree(root.left);
+            root.right = invertTree(root.right);
+        }
         return root;
     }
 }
\ No newline at end of file
diff --git a/java/228. Summary Ranges.java b/java/228. Summary Ranges.java
index d114229..021a207 100644
--- a/java/228. Summary Ranges.java	
+++ b/java/228. Summary Ranges.java	
@@ -1,31 +1,31 @@
-public class Solution {
+public class Solution {
     public List<String> summaryRanges(int[] nums) {
-    	List<String> list=new ArrayList<String>();
-    	if (nums.length==0) {
-			return list;
-		}
+        List<String> list=new ArrayList<String>();
+        if (nums.length==0) {
+            return list;
+        }
         int k=0;
         if (nums.length==1) {
-			list.add(""+nums[k]);
-			return list;
-		}
-    	for (int i = 1; i < nums.length; i++) {
-    		if(nums[i]==nums[i-1]+1){
-    			continue;
-    		}else {
-    			if (i-1==k) {
-    				list.add(""+nums[k]);
-				}else {
-					list.add(""+nums[k]+"->"+nums[i-1]);
-				}
-				k=i;
-			}
-		}
-    	if (k==nums.length-1) {
-    		list.add(""+nums[k]);
-		}else {
-			list.add(""+nums[k]+"->"+nums[nums.length-1]);
-		}
-    	return list;
+            list.add(""+nums[k]);
+            return list;
+        }
+        for (int i = 1; i < nums.length; i++) {
+            if(nums[i]==nums[i-1]+1){
+                continue;
+            }else {
+                if (i-1==k) {
+                    list.add(""+nums[k]);
+                }else {
+                    list.add(""+nums[k]+"->"+nums[i-1]);
+                }
+                k=i;
+            }
+        }
+        if (k==nums.length-1) {
+            list.add(""+nums[k]);
+        }else {
+            list.add(""+nums[k]+"->"+nums[nums.length-1]);
+        }
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/229. Majority Element II.java b/java/229. Majority Element II.java
index a690b12..628ec8d 100644
--- a/java/229. Majority Element II.java	
+++ b/java/229. Majority Element II.java	
@@ -1,36 +1,36 @@
 public class Solution {
     public List<Integer> majorityElement(int[] nums) {
-    	List<Integer> ans=new ArrayList<Integer>();
-    	if (nums.length==0) {
-    		return ans;
-		}
-    	if (nums.length==1) {
-    		ans.add(nums[0]);
-    		return ans;
-		}
-    	if (nums.length==2) {
-    		ans.add(nums[0]);
-    		if (nums[1]!=nums[0]) {
-				ans.add(nums[1]);
-			}
-    		return ans;
-		}
-    	Arrays.sort(nums);
-    	int l=nums.length/3;
+        List<Integer> ans=new ArrayList<Integer>();
+        if (nums.length==0) {
+            return ans;
+        }
+        if (nums.length==1) {
+            ans.add(nums[0]);
+            return ans;
+        }
+        if (nums.length==2) {
+            ans.add(nums[0]);
+            if (nums[1]!=nums[0]) {
+                ans.add(nums[1]);
+            }
+            return ans;
+        }
+        Arrays.sort(nums);
+        int l=nums.length/3;
         for (int i = 0; i < nums.length-l;) {
-			if (nums[i+l]==nums[i]) {
-				ans.add(nums[i]);
-				i+=l;
-			}else {
-				i++;
-			}
-		}
+            if (nums[i+l]==nums[i]) {
+                ans.add(nums[i]);
+                i+=l;
+            }else {
+                i++;
+            }
+        }
         for (int i = 1; i < ans.size(); i++) {
-			if (ans.get(i)==ans.get(i-1)) {
-				ans.remove(i);
-				i--;
-			}
-		}
+            if (ans.get(i)==ans.get(i-1)) {
+                ans.remove(i);
+                i--;
+            }
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/230. Kth Smallest Element in a BST.java b/java/230. Kth Smallest Element in a BST.java
index 2e582c2..4e0a7b0 100644
--- a/java/230. Kth Smallest Element in a BST.java	
+++ b/java/230. Kth Smallest Element in a BST.java	
@@ -11,17 +11,17 @@ public class Solution {
     public int kthSmallest(TreeNode root, int k) {
         int left=f(root.left);
         if (k==left+1) {
-			return root.val;
-		}
+            return root.val;
+        }
         if (k<=left) {
-			return kthSmallest(root.left,k);
-		}
+            return kthSmallest(root.left,k);
+        }
         return kthSmallest(root.right,k-left-1);
     }
     public int f(TreeNode root){
-    	if (root!=null) {
-			return 1+f(root.left)+f(root.right);
-		}
-    	return 0;
+        if (root!=null) {
+            return 1+f(root.left)+f(root.right);
+        }
+        return 0;
     }
 }
\ No newline at end of file
diff --git a/java/234. Palindrome Linked List.java b/java/234. Palindrome Linked List.java
index ddc3a0a..b65369c 100644
--- a/java/234. Palindrome Linked List.java	
+++ b/java/234. Palindrome Linked List.java	
@@ -9,39 +9,39 @@
 public class Solution {
     public boolean isPalindrome(ListNode head) {
         if (head==null||head.next==null) {
-			return true;
-		}
+            return true;
+        }
         ListNode slow=head;
         ListNode fast=head;
         while (fast!=null&&fast.next!=null) {
-			slow=slow.next;
-			fast=fast.next.next;
-		}
+            slow=slow.next;
+            fast=fast.next.next;
+        }
         ListNode test=f(slow);
         while (test!=null) {
-			if (test.val!=head.val) {
-				return false;
-			}
-			test=test.next;
-			head=head.next;
-		}
+            if (test.val!=head.val) {
+                return false;
+            }
+            test=test.next;
+            head=head.next;
+        }
         
         return true;
     }
     //原地翻转链表
     public ListNode f(ListNode node){
-    	if (node==null||node.next==null) {
-			return node;
-		}
-    	ListNode l=node.next;
-    	ListNode h;
-    	node.next=null;
-    	while (l!=null) {
-			h=l.next;
-			l.next=node;
-			node=l;
-			l=h;
-		}
-    	return node;
+        if (node==null||node.next==null) {
+            return node;
+        }
+        ListNode l=node.next;
+        ListNode h;
+        node.next=null;
+        while (l!=null) {
+            h=l.next;
+            l.next=node;
+            node=l;
+            l=h;
+        }
+        return node;
     }
 }
\ No newline at end of file
diff --git a/java/235. Lowest Common Ancestor of a Binary Search Tree.java b/java/235. Lowest Common Ancestor of a Binary Search Tree.java
index 3b7793c..73804e7 100644
--- a/java/235. Lowest Common Ancestor of a Binary Search Tree.java	
+++ b/java/235. Lowest Common Ancestor of a Binary Search Tree.java	
@@ -9,22 +9,22 @@
  */
 public class Solution {
     public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
-    	if (root==p) {
-			return p;
-		}
-    	if (root==q) {
-			return q;
-		}
+        if (root==p) {
+            return p;
+        }
+        if (root==q) {
+            return q;
+        }
         int ip=root.val-p.val;
         int iq=root.val-q.val;
         if (ip>0!=iq>0) {
-        	return root;
-		}else {
-			if (ip>0) {
-				return lowestCommonAncestor(root.left,p,q);
-			}else {
-				return lowestCommonAncestor(root.right,p,q);
-			}
-		}
+            return root;
+        }else {
+            if (ip>0) {
+                return lowestCommonAncestor(root.left,p,q);
+            }else {
+                return lowestCommonAncestor(root.right,p,q);
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/236. Lowest Common Ancestor of a Binary Tree.java b/java/236. Lowest Common Ancestor of a Binary Tree.java
index cf02705..e8a42b1 100644
--- a/java/236. Lowest Common Ancestor of a Binary Tree.java	
+++ b/java/236. Lowest Common Ancestor of a Binary Tree.java	
@@ -14,33 +14,33 @@ public TreeNode lowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
         String sq=f(root,q);
         sq=sq.substring(0,sq.length()-1);
         for (int i = 0; i < Math.min(sp.length(), sq.length()); i++) {
-			String kp=sp.substring(i,i+1);
-			String kq=sq.substring(i,i+1);
-			if (kp.equals(kq)) {
-				if (kp.equals("0")) {
-					root=root.left;
-				}else {
-					root=root.right;
-				}
-			}else {
-				return root;
-			}
-		}
-    	return root;
+            String kp=sp.substring(i,i+1);
+            String kq=sq.substring(i,i+1);
+            if (kp.equals(kq)) {
+                if (kp.equals("0")) {
+                    root=root.left;
+                }else {
+                    root=root.right;
+                }
+            }else {
+                return root;
+            }
+        }
+        return root;
     }
     public String f(TreeNode root, TreeNode p){
-    	if (root==null) {
-			return "3";
-		}
-    	if (root==p) {
-			return "2";
-		}
-    	String left=f(root.left,p);
-    	String right=f(root.right,p);
-    	if (left.substring(left.length()-1,left.length()).equals("2")) {
-			return "0"+left;
-		}else {
-			return "1"+right;
-		}
+        if (root==null) {
+            return "3";
+        }
+        if (root==p) {
+            return "2";
+        }
+        String left=f(root.left,p);
+        String right=f(root.right,p);
+        if (left.substring(left.length()-1,left.length()).equals("2")) {
+            return "0"+left;
+        }else {
+            return "1"+right;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/238. Product of Array Except Self.java b/java/238. Product of Array Except Self.java
index dc8f9f9..c6e7332 100644
--- a/java/238. Product of Array Except Self.java	
+++ b/java/238. Product of Array Except Self.java	
@@ -1,33 +1,33 @@
 public class Solution {
     public int[] productExceptSelf(int[] nums) {
-    	int length=nums.length;
-    	int k=0;
-    	boolean flag=true;
-    	int product=1;
+        int length=nums.length;
+        int k=0;
+        boolean flag=true;
+        int product=1;
         for (int i = 0; i < length; i++) {
-        	if (nums[i]==0) {
-				if (flag) {
-					k=i;
-					flag=false;
-				}else {
-					int[] answer=new int[length];
-					for (int j = 0; j <length; j++) {
-						answer[j]=0;
-					}
-					return answer;
-				}
-			}else {
-				product*=nums[i];
-			}
-		}
+            if (nums[i]==0) {
+                if (flag) {
+                    k=i;
+                    flag=false;
+                }else {
+                    int[] answer=new int[length];
+                    for (int j = 0; j <length; j++) {
+                        answer[j]=0;
+                    }
+                    return answer;
+                }
+            }else {
+                product*=nums[i];
+            }
+        }
         int[] answer=new int[length];
         if (flag) {
-			for (int i = 0; i < length; i++) {
-				answer[i]=product/nums[i];
-			}
-		}else {
-			answer[k]=product;
-		}
+            for (int i = 0; i < length; i++) {
+                answer[i]=product/nums[i];
+            }
+        }else {
+            answer[k]=product;
+        }
         return answer;
     }
 }
\ No newline at end of file
diff --git a/java/239. Sliding Window Maximum.java b/java/239. Sliding Window Maximum.java
index 364b8d1..525d642 100644
--- a/java/239. Sliding Window Maximum.java	
+++ b/java/239. Sliding Window Maximum.java	
@@ -1,38 +1,38 @@
 public class Solution {
     public int[] maxSlidingWindow(int[] nums, int k) {
-    	if (nums.length==0||k==0||k==1) {
-			return nums;
-		}
+        if (nums.length==0||k==0||k==1) {
+            return nums;
+        }
         List<Integer> maxList=new ArrayList<Integer>();
         for (int i = 0; i < k; i++) {
-			while (maxList.size()!=0) {
-				if (maxList.get(maxList.size()-1)<nums[i]) {
-					maxList.remove(maxList.size()-1);
-				}else {
-					break;
-				}
-			}
-			maxList.add(nums[i]);
-		}
+            while (maxList.size()!=0) {
+                if (maxList.get(maxList.size()-1)<nums[i]) {
+                    maxList.remove(maxList.size()-1);
+                }else {
+                    break;
+                }
+            }
+            maxList.add(nums[i]);
+        }
         int[] ans=new int[nums.length-k+1];
         ans[0]=maxList.get(0);
         for (int i = k; i < nums.length; i++) {
-        	//排队出去一个
-        	if (nums[i-k]==maxList.get(0)) {
-				maxList.remove(0);
-			}
-			//排队进来一个
-        	while (maxList.size()!=0) {
-				if (maxList.get(maxList.size()-1)<nums[i]) {
-					maxList.remove(maxList.size()-1);
-				}else {
-					break;
-				}
-			}
-			maxList.add(nums[i]);
-			//赋值
-			ans[i-k+1]=maxList.get(0);
-		}
+            //排队出去一个
+            if (nums[i-k]==maxList.get(0)) {
+                maxList.remove(0);
+            }
+            //排队进来一个
+            while (maxList.size()!=0) {
+                if (maxList.get(maxList.size()-1)<nums[i]) {
+                    maxList.remove(maxList.size()-1);
+                }else {
+                    break;
+                }
+            }
+            maxList.add(nums[i]);
+            //赋值
+            ans[i-k+1]=maxList.get(0);
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/240. Search a 2D Matrix II.java b/java/240. Search a 2D Matrix II.java
index 47dd9e5..d2155e3 100644
--- a/java/240. Search a 2D Matrix II.java	
+++ b/java/240. Search a 2D Matrix II.java	
@@ -1,17 +1,17 @@
 public class Solution {
     public boolean searchMatrix(int[][] matrix, int target) {
-    	int x=matrix.length-1;
-    	int y=0;
-    	while (x>=0&&y<matrix[x].length) {
-			if (matrix[x][y]==target) {
-				return true;
-			}
-			if (matrix[x][y]>target) {
-				x--;
-			}else {
-				y++;
-			}
-		}
-    	return false;
+        int x=matrix.length-1;
+        int y=0;
+        while (x>=0&&y<matrix[x].length) {
+            if (matrix[x][y]==target) {
+                return true;
+            }
+            if (matrix[x][y]>target) {
+                x--;
+            }else {
+                y++;
+            }
+        }
+        return false;
     }
 }
\ No newline at end of file
diff --git a/java/242. Valid Anagram.java b/java/242. Valid Anagram.java
index f118af1..707d51e 100644
--- a/java/242. Valid Anagram.java	
+++ b/java/242. Valid Anagram.java	
@@ -1,29 +1,29 @@
 public class Solution {
     public boolean isAnagram(String s, String t) {
         if (s.length()!=t.length()) {
-			return false;
-		}
+            return false;
+        }
         Map<Character,Integer> smap=new HashMap<Character, Integer>();
         Map<Character,Integer> tmap=new HashMap<Character, Integer>();
         char[] cs=s.toCharArray();
         char[] ct=t.toCharArray();
         for (int i = 0; i < ct.length; i++) {
-			if (smap.get(cs[i])!=null) {
-				smap.put(cs[i], smap.get(cs[i])+1);
-			}else {
-				smap.put(cs[i], 1);
-			}
-			if (tmap.get(ct[i])!=null) {
-				tmap.put(ct[i], tmap.get(ct[i])+1);
-			}else {
-				tmap.put(ct[i], 1);
-			}
-		}
+            if (smap.get(cs[i])!=null) {
+                smap.put(cs[i], smap.get(cs[i])+1);
+            }else {
+                smap.put(cs[i], 1);
+            }
+            if (tmap.get(ct[i])!=null) {
+                tmap.put(ct[i], tmap.get(ct[i])+1);
+            }else {
+                tmap.put(ct[i], 1);
+            }
+        }
         for (int i = 0; i < ct.length; i++) {
-			if (!tmap.get(ct[i]).equals(smap.get(ct[i]))) {
-				return false;
-			}
-		}
+            if (!tmap.get(ct[i]).equals(smap.get(ct[i]))) {
+                return false;
+            }
+        }
         return true;
     }
 }
\ No newline at end of file
diff --git a/java/257. Binary Tree Paths.java b/java/257. Binary Tree Paths.java
index c214ba5..2de102c 100644
--- a/java/257. Binary Tree Paths.java	
+++ b/java/257. Binary Tree Paths.java	
@@ -9,44 +9,44 @@
  */
 public class Solution {
     public List<String> binaryTreePaths(TreeNode root) {
-    	List<String> ansList=new ArrayList<String>();
+        List<String> ansList=new ArrayList<String>();
         if (root!=null) {
-			List<List<TreeNode>> totalList=new ArrayList<List<TreeNode>>();
-			List<TreeNode> initList=new ArrayList<TreeNode>();
-			initList.add(root);
-			totalList.add(initList);
-			for (int i = 0; i < totalList.size(); i++) {
-				List<TreeNode> list=totalList.get(i);
-				TreeNode node=list.get(list.size()-1);
-				boolean flag=false;
-				if (node.left!=null) {
-					List<TreeNode> leftList=new ArrayList<TreeNode>();
-					leftList.addAll(list);
-					leftList.add(node.left);
-					totalList.add(leftList);
-					flag=true;
-				}
-				if (node.right!=null) {
-					List<TreeNode> rightList=new ArrayList<TreeNode>();
-					rightList.addAll(list);
-					rightList.add(node.right);
-					totalList.add(rightList);
-					flag=true;
-				}
-				if (flag) {
-					totalList.remove(i);
-					i--;
-				}
-			}
-			for (int i = 0; i < totalList.size(); i++) {
-				List<TreeNode> list=totalList.get(i);
-				String ans=""+list.get(0).val;
-				for (int j = 1; j < list.size(); j++) {
-					ans+=("->"+list.get(j).val);
-				}
-				ansList.add(ans);
-			}
-		}
-    	return ansList;
+            List<List<TreeNode>> totalList=new ArrayList<List<TreeNode>>();
+            List<TreeNode> initList=new ArrayList<TreeNode>();
+            initList.add(root);
+            totalList.add(initList);
+            for (int i = 0; i < totalList.size(); i++) {
+                List<TreeNode> list=totalList.get(i);
+                TreeNode node=list.get(list.size()-1);
+                boolean flag=false;
+                if (node.left!=null) {
+                    List<TreeNode> leftList=new ArrayList<TreeNode>();
+                    leftList.addAll(list);
+                    leftList.add(node.left);
+                    totalList.add(leftList);
+                    flag=true;
+                }
+                if (node.right!=null) {
+                    List<TreeNode> rightList=new ArrayList<TreeNode>();
+                    rightList.addAll(list);
+                    rightList.add(node.right);
+                    totalList.add(rightList);
+                    flag=true;
+                }
+                if (flag) {
+                    totalList.remove(i);
+                    i--;
+                }
+            }
+            for (int i = 0; i < totalList.size(); i++) {
+                List<TreeNode> list=totalList.get(i);
+                String ans=""+list.get(0).val;
+                for (int j = 1; j < list.size(); j++) {
+                    ans+=("->"+list.get(j).val);
+                }
+                ansList.add(ans);
+            }
+        }
+        return ansList;
     }
 }
\ No newline at end of file
diff --git a/java/263. Ugly Number.java b/java/263. Ugly Number.java
index baa9b62..1745bf5 100644
--- a/java/263. Ugly Number.java	
+++ b/java/263. Ugly Number.java	
@@ -1,19 +1,19 @@
 public class Solution {
     public boolean isUgly(int num) {
-    	if (num==0) {
-			return false;
-		}
+        if (num==0) {
+            return false;
+        }
         while (num!=1) {
-			if (num%2==0) {
-				num/=2;
-			}else if (num%3==0) {
-				num/=3;
-			}else if (num%5==0) {
-				num/=5;
-			}else {
-				return false;
-			}
-		}
-    	return true;
+            if (num%2==0) {
+                num/=2;
+            }else if (num%3==0) {
+                num/=3;
+            }else if (num%5==0) {
+                num/=5;
+            }else {
+                return false;
+            }
+        }
+        return true;
     }
 }
\ No newline at end of file
diff --git a/java/264. Ugly Number II.java b/java/264. Ugly Number II.java
index 3eaff55..49cb7b7 100644
--- a/java/264. Ugly Number II.java	
+++ b/java/264. Ugly Number II.java	
@@ -1,51 +1,51 @@
 public class Solution {
     public int nthUglyNumber(int n) {
         if (n<7) {
-			return n;
-		}
+            return n;
+        }
         List<Integer> list=new ArrayList<Integer>();
         list.add(1);
         list.add(2);
         list.add(3);
         while (list.size()<n) {
-			list=a(list);
-		}
+            list=a(list);
+        }
         return list.get(n-1);
     }
     public List<Integer> a(List<Integer> list){
-    	int end=list.get(list.size()-1);
-    	int a2=0;
-    	int a3=0;
-    	int a5=0;
-    	int k=0;
-    	for (int i = 0; i < list.size(); i++) {
-			if (list.get(i)*5>end) {
-				a5=list.get(i)*5;
-				k=i;
-				break;
-			}
-		}
-    	for (int i = k; i < list.size(); i++) {
-			if (list.get(i)*3>end) {
-				a3=list.get(i)*3;
-				k=i;
-				break;
-			}
-		}
-    	for (int i = k; i < list.size(); i++) {
-			if (list.get(i)*2>end) {
-				a2=list.get(i)*2;
-				k=i;
-				break;
-			}
-		}
-    	int a=0;
-    	if (a2<a3) {
-			a=a2<a5?a2:a5;
-		}else {
-			a=a3<a5?a3:a5;
-		}
-    	list.add(a);
-    	return list;
+        int end=list.get(list.size()-1);
+        int a2=0;
+        int a3=0;
+        int a5=0;
+        int k=0;
+        for (int i = 0; i < list.size(); i++) {
+            if (list.get(i)*5>end) {
+                a5=list.get(i)*5;
+                k=i;
+                break;
+            }
+        }
+        for (int i = k; i < list.size(); i++) {
+            if (list.get(i)*3>end) {
+                a3=list.get(i)*3;
+                k=i;
+                break;
+            }
+        }
+        for (int i = k; i < list.size(); i++) {
+            if (list.get(i)*2>end) {
+                a2=list.get(i)*2;
+                k=i;
+                break;
+            }
+        }
+        int a=0;
+        if (a2<a3) {
+            a=a2<a5?a2:a5;
+        }else {
+            a=a3<a5?a3:a5;
+        }
+        list.add(a);
+        return list;
     }
 }
\ No newline at end of file
diff --git a/java/268. Missing Number.java b/java/268. Missing Number.java
index a16cd96..d956dbb 100644
--- a/java/268. Missing Number.java	
+++ b/java/268. Missing Number.java	
@@ -1,9 +1,9 @@
 public class Solution {
     public int missingNumber(int[] nums) {
-    	int ans=nums.length;
+        int ans=nums.length;
         for (int i = 0; i < nums.length; i++) {
-        	ans=ans-nums[i]+i;
-		}
+            ans=ans-nums[i]+i;
+        }
         return ans;
     }
 }
\ No newline at end of file
diff --git a/java/273. Integer to English Words.java b/java/273. Integer to English Words.java
index a3a9c26..f979fe1 100644
--- a/java/273. Integer to English Words.java	
+++ b/java/273. Integer to English Words.java	
@@ -1,109 +1,109 @@
 public class Solution {
     public String numberToWords(int num) {
         if (num==0) {
-			return "Zero";
-		}
-    	Map<String, String> map=new HashMap<String, String>();
-    	map.put("1", "One");
-    	map.put("2", "Two");
-    	map.put("3", "Three");
-    	map.put("4", "Four");
-    	map.put("5", "Five");
-    	map.put("6", "Six");
-    	map.put("7", "Seven");
-    	map.put("8", "Eight");
-    	map.put("9", "Nine");
-    	map.put("10", "Ten");
-    	map.put("11", "Eleven");
-    	map.put("12", "Twelve");
-    	map.put("13", "Thirteen");
-    	map.put("14", "Fourteen");
-    	map.put("15", "Fifteen");
-    	map.put("16", "Sixteen");
-    	map.put("17", "Seventeen");
-    	map.put("18", "Eighteen");
-    	map.put("19", "Nineteen");
-    	map.put("20", "Twenty");
-    	map.put("30", "Thirty");
-    	map.put("40", "Forty");
-    	map.put("50", "Fifty");
-    	map.put("60", "Sixty");
-    	map.put("70", "Seventy");
-    	map.put("80", "Eighty");
-    	map.put("90", "Ninety");
+            return "Zero";
+        }
+        Map<String, String> map=new HashMap<String, String>();
+        map.put("1", "One");
+        map.put("2", "Two");
+        map.put("3", "Three");
+        map.put("4", "Four");
+        map.put("5", "Five");
+        map.put("6", "Six");
+        map.put("7", "Seven");
+        map.put("8", "Eight");
+        map.put("9", "Nine");
+        map.put("10", "Ten");
+        map.put("11", "Eleven");
+        map.put("12", "Twelve");
+        map.put("13", "Thirteen");
+        map.put("14", "Fourteen");
+        map.put("15", "Fifteen");
+        map.put("16", "Sixteen");
+        map.put("17", "Seventeen");
+        map.put("18", "Eighteen");
+        map.put("19", "Nineteen");
+        map.put("20", "Twenty");
+        map.put("30", "Thirty");
+        map.put("40", "Forty");
+        map.put("50", "Fifty");
+        map.put("60", "Sixty");
+        map.put("70", "Seventy");
+        map.put("80", "Eighty");
+        map.put("90", "Ninety");
         String str=String.valueOf(num);
         int length=str.length();
         List<String> list=new ArrayList<String>();
         while (str.length()>3) {
-			list.add(str.substring(length-3,length));
-			str=str.substring(0,length-3);
-			length=str.length();
-		}
+            list.add(str.substring(length-3,length));
+            str=str.substring(0,length-3);
+            length=str.length();
+        }
         list.add(str);
         System.out.println("list.size()="+list.size());
         List<String> ansList=new ArrayList<String>();
         for (int i = 0; i < list.size(); i++) {
-			ansList.add(f(list.get(i),map));
-		}
+            ansList.add(f(list.get(i),map));
+        }
         String ans="";
         if (ansList.size()!=0) {
-			ans=ansList.get(0);
-			ansList.remove(0);
-		}
+            ans=ansList.get(0);
+            ansList.remove(0);
+        }
         if (ansList.size()!=0) {
-        	if (ansList.get(0).length()!=0) {
-        		if (ans.length()==0) {
-        			ans=ansList.get(0)+" Thousand";
-        		}else {
-        			ans=ansList.get(0)+" Thousand "+ans;
-        		}
-			}
-			ansList.remove(0);
-		}
+            if (ansList.get(0).length()!=0) {
+                if (ans.length()==0) {
+                    ans=ansList.get(0)+" Thousand";
+                }else {
+                    ans=ansList.get(0)+" Thousand "+ans;
+                }
+            }
+            ansList.remove(0);
+        }
         if (ansList.size()!=0) {
-        	if (ansList.get(0).length()!=0) {
-        		if (ans.length()==0) {
-        			ans=ansList.get(0)+" Million";
-        		}else {
-        			ans=ansList.get(0)+" Million "+ans;
-        		}
-			}
-			ansList.remove(0);
-		}
+            if (ansList.get(0).length()!=0) {
+                if (ans.length()==0) {
+                    ans=ansList.get(0)+" Million";
+                }else {
+                    ans=ansList.get(0)+" Million "+ans;
+                }
+            }
+            ansList.remove(0);
+        }
         if (ansList.size()!=0) {
-        	if (ansList.get(0).length()!=0){
-        		if (ans.length()==0) {
-        			ans=ansList.get(0)+" Billion";
-        		}else {
-        			ans=ansList.get(0)+" Billion "+ans;
-        		}
-        	}
-			ansList.remove(0);
-		}
-    	return ans;
+            if (ansList.get(0).length()!=0){
+                if (ans.length()==0) {
+                    ans=ansList.get(0)+" Billion";
+                }else {
+                    ans=ansList.get(0)+" Billion "+ans;
+                }
+            }
+            ansList.remove(0);
+        }
+        return ans;
     }
     public String f(String str,Map<String, String> map){
-    	StringBuffer sb=new StringBuffer();
-    	int i=Integer.parseInt(str);
-    	if (i>=100) {
-			sb.append(map.get(""+i/100));
-			sb.append(" Hundred");
-		}
-    	i=i%100;
-    	if (i!=0) {
-    		if (sb.length()!=0) {
-				sb.append(" ");
-			}
-			if (i%100<20) {
-				sb.append(map.get(""+i));
-			}else {
-				sb.append(map.get(""+(i-i%10)));
-				if (i%10!=0) {
-					sb.append(" ");
-					sb.append(map.get(""+i%10));
-				}
-			}
-		}
-    	return sb.toString();
+        StringBuffer sb=new StringBuffer();
+        int i=Integer.parseInt(str);
+        if (i>=100) {
+            sb.append(map.get(""+i/100));
+            sb.append(" Hundred");
+        }
+        i=i%100;
+        if (i!=0) {
+            if (sb.length()!=0) {
+                sb.append(" ");
+            }
+            if (i%100<20) {
+                sb.append(map.get(""+i));
+            }else {
+                sb.append(map.get(""+(i-i%10)));
+                if (i%10!=0) {
+                    sb.append(" ");
+                    sb.append(map.get(""+i%10));
+                }
+            }
+        }
+        return sb.toString();
     }
 }
\ No newline at end of file
diff --git a/java/274. H-Index.java b/java/274. H-Index.java
index 5e4339d..30a06e9 100644
--- a/java/274. H-Index.java	
+++ b/java/274. H-Index.java	
@@ -3,12 +3,12 @@ public int hIndex(int[] citations) {
         Arrays.sort(citations);
         int ans=0;
         for (int i = citations.length-1; i >=0 ; i--) {
-			if (citations[i]>ans) {
-				ans++;
-			}else {
-				return ans;
-			}
-		}
-    	return ans;
+            if (citations[i]>ans) {
+                ans++;
+            }else {
+                return ans;
+            }
+        }
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/275. H-Index II.java b/java/275. H-Index II.java
index 2d08e2b..aacb20a 100644
--- a/java/275. H-Index II.java	
+++ b/java/275. H-Index II.java	
@@ -1,33 +1,33 @@
 public class Solution {
     public int hIndex(int[] citations) {
-    	if (citations.length==0) {
-			return 0;
-		}
+        if (citations.length==0) {
+            return 0;
+        }
         Arrays.sort(citations);
         int s=0;
         int e=citations.length-1;
         int m=(s+e)/2;
         int l=citations.length;
         while (e-s>1) {
-        	if (l<citations[s]+s) {
-				return l;
-			}
-        	if (l==citations[m]+m) {
-				return l-m;
-			}
-        	if (l>citations[m]+m) {
-				s=m;
-			}else {
-				e=m;
-			}
-        	m=(s+e)/2;
-		}
+            if (l<citations[s]+s) {
+                return l;
+            }
+            if (l==citations[m]+m) {
+                return l-m;
+            }
+            if (l>citations[m]+m) {
+                s=m;
+            }else {
+                e=m;
+            }
+            m=(s+e)/2;
+        }
         if (l>citations[e]+e) {
-			return l-e-1;
-		}else if(l>citations[s]+s){
-			return l-e;
-		}else{
-		    return l-s;
-		}
+            return l-e-1;
+        }else if(l>citations[s]+s){
+            return l-e;
+        }else{
+            return l-s;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/279. Perfect Squares.java b/java/279. Perfect Squares.java
index 44ec35f..14a479b 100644
--- a/java/279. Perfect Squares.java	
+++ b/java/279. Perfect Squares.java	
@@ -1,24 +1,24 @@
 public class Solution {
-	Map<Integer, Integer> map=new HashMap<Integer, Integer>();
+    Map<Integer, Integer> map=new HashMap<Integer, Integer>();
     public int numSquares(int n) {
-    	if (n<4) {
-			return n;
-		}
+        if (n<4) {
+            return n;
+        }
         if (map.get(n)==null) {
-			int s=(int) Math.sqrt(n);
-			if (s*s==n) {
-				return 1;
-			}
-			int ans=numSquares(n-s*s);
-			//凭感觉处理了一下测试的最小值
-			for (int i = s-1; i >=Math.max(s/2, 1); i--) {
-				int t=numSquares(n-i*i);
-				if (t<ans) {
-					ans=t;
-				}
-			}
-			map.put(n, 1+ans);
-		}
+            int s=(int) Math.sqrt(n);
+            if (s*s==n) {
+                return 1;
+            }
+            int ans=numSquares(n-s*s);
+            //凭感觉处理了一下测试的最小值
+            for (int i = s-1; i >=Math.max(s/2, 1); i--) {
+                int t=numSquares(n-i*i);
+                if (t<ans) {
+                    ans=t;
+                }
+            }
+            map.put(n, 1+ans);
+        }
         return map.get(n);
     }
 }
\ No newline at end of file
diff --git a/java/283. Move Zeroes.java b/java/283. Move Zeroes.java
index d48362d..4a9749a 100644
--- a/java/283. Move Zeroes.java	
+++ b/java/283. Move Zeroes.java	
@@ -1,23 +1,23 @@
 public class Solution {
     public void moveZeroes(int[] nums) {
-    	if (nums!=null&&nums.length!=1) {
-    		int b=-1;
-			for (int i = 0; i < nums.length; i++) {
-				if (nums[i]==0) {
-					b=i;
-					break;
-				}
-			}
-			if (b!=nums.length-1&&b!=-1) {
-				for (int i = b+1; i < nums.length; i++) {
-					int k=nums[i];
-					if (k!=0) {
-						nums[b]=k;
-						nums[i]=0;
-						b++;
-					}
-				}
-			}
-		}
+        if (nums!=null&&nums.length!=1) {
+            int b=-1;
+            for (int i = 0; i < nums.length; i++) {
+                if (nums[i]==0) {
+                    b=i;
+                    break;
+                }
+            }
+            if (b!=nums.length-1&&b!=-1) {
+                for (int i = b+1; i < nums.length; i++) {
+                    int k=nums[i];
+                    if (k!=0) {
+                        nums[b]=k;
+                        nums[i]=0;
+                        b++;
+                    }
+                }
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/284. Peeking Iterator.java b/java/284. Peeking Iterator.java
index 85429c1..d6be603 100644
--- a/java/284. Peeking Iterator.java	
+++ b/java/284. Peeking Iterator.java	
@@ -3,29 +3,29 @@
 class PeekingIterator implements Iterator<Integer> {
     public List<Integer> list=new ArrayList<Integer>();
 
-	public PeekingIterator(Iterator<Integer> iterator) {
-	    // initialize any member here.
-	    while(iterator.hasNext()){
-	        list.add(iterator.next());
-	    }
-	}
+    public PeekingIterator(Iterator<Integer> iterator) {
+        // initialize any member here.
+        while(iterator.hasNext()){
+            list.add(iterator.next());
+        }
+    }
 
     // Returns the next element in the iteration without advancing the iterator.
-	public Integer peek() {
+    public Integer peek() {
         return list.get(0);
-	}
+    }
 
-	// hasNext() and next() should behave the same as in the Iterator interface.
-	// Override them if needed.
-	@Override
-	public Integer next() {
-	    Integer i=list.get(0);
-	    list.remove(0);
-	    return i;
-	}
+    // hasNext() and next() should behave the same as in the Iterator interface.
+    // Override them if needed.
+    @Override
+    public Integer next() {
+        Integer i=list.get(0);
+        list.remove(0);
+        return i;
+    }
 
-	@Override
-	public boolean hasNext() {
-	    return list.size()>0;
-	}
+    @Override
+    public boolean hasNext() {
+        return list.size()>0;
+    }
 }
\ No newline at end of file
diff --git a/java/287. Find the Duplicate Number.java b/java/287. Find the Duplicate Number.java
index a3d6b83..87c5b5b 100644
--- a/java/287. Find the Duplicate Number.java	
+++ b/java/287. Find the Duplicate Number.java	
@@ -1,33 +1,33 @@
 public class Solution {
     public int findDuplicate(int[] nums) {
-    	return f(nums,0,nums.length-1);
+        return f(nums,0,nums.length-1);
     }
     public int f(int[] nums,int s,int e){
-    	if (s==e) {
-			return 0;
-		}
-    	if (s+1==e) {
-			if (nums[s]==nums[e]) {
-				return nums[s];
-			}
-			return 0;
-		}
-    	int m=(s+e)/2;
-    	int a=f(nums,s,m);
-    	int b=f(nums,m+1,e);
-    	if (a!=0) {
-			return a;
-		}
-    	if (b!=0) {
-			return b;
-		}
-    	for (int i = s; i <=m; i++) {
-			for (int j = m+1; j <=e; j++) {
-				if (nums[i]==nums[j]) {
-					return nums[j];
-				}
-			}
-		}
-    	return 0;
+        if (s==e) {
+            return 0;
+        }
+        if (s+1==e) {
+            if (nums[s]==nums[e]) {
+                return nums[s];
+            }
+            return 0;
+        }
+        int m=(s+e)/2;
+        int a=f(nums,s,m);
+        int b=f(nums,m+1,e);
+        if (a!=0) {
+            return a;
+        }
+        if (b!=0) {
+            return b;
+        }
+        for (int i = s; i <=m; i++) {
+            for (int j = m+1; j <=e; j++) {
+                if (nums[i]==nums[j]) {
+                    return nums[j];
+                }
+            }
+        }
+        return 0;
     }
 }
\ No newline at end of file
diff --git a/java/289. Game of Life.java b/java/289. Game of Life.java
index 79325d0..e28dc84 100644
--- a/java/289. Game of Life.java	
+++ b/java/289. Game of Life.java	
@@ -2,29 +2,29 @@ public class Solution {
     public void gameOfLife(int[][] board) {
         int[][] newboard=new int[board.length][board[0].length];
         for (int i = 0; i < board.length; i++) {
-        	for (int j = 0; j < board[i].length; j++) {
-				int k=board[i][j];
-				int v=f(board,i,j);
-				System.out.println("v="+v);
-				if (v==3||(v==2&&k==1)) {
-					System.out.println("true");
-					newboard[i][j]=1;
-				}
-			}
-		}
+            for (int j = 0; j < board[i].length; j++) {
+                int k=board[i][j];
+                int v=f(board,i,j);
+                System.out.println("v="+v);
+                if (v==3||(v==2&&k==1)) {
+                    System.out.println("true");
+                    newboard[i][j]=1;
+                }
+            }
+        }
         for (int i = 0; i < board.length; i++) {
-        	for (int j = 0; j < board[i].length; j++) {
-				board[i][j]=newboard[i][j];
-			}
-		}
+            for (int j = 0; j < board[i].length; j++) {
+                board[i][j]=newboard[i][j];
+            }
+        }
     }
     public int f(int[][] board,int x,int y){
-    	return g(board,x-1,y-1)+g(board,x-1,y)+g(board,x-1,y+1)+g(board,x,y-1)+g(board,x,y+1)+g(board,x+1,y-1)+g(board,x+1,y)+g(board,x+1,y+1);
+        return g(board,x-1,y-1)+g(board,x-1,y)+g(board,x-1,y+1)+g(board,x,y-1)+g(board,x,y+1)+g(board,x+1,y-1)+g(board,x+1,y)+g(board,x+1,y+1);
     }
     public int g(int[][] board,int x,int y){
-    	if (x>=0&&x<board.length&&y>=0&&y<board[x].length) {
-			return board[x][y];
-		}
-    	return 0;
+        if (x>=0&&x<board.length&&y>=0&&y<board[x].length) {
+            return board[x][y];
+        }
+        return 0;
     }
 }
\ No newline at end of file
diff --git a/java/290. Word Pattern.java b/java/290. Word Pattern.java
index 5352556..3e26a90 100644
--- a/java/290. Word Pattern.java	
+++ b/java/290. Word Pattern.java	
@@ -2,25 +2,25 @@ public class Solution {
     public boolean wordPattern(String pattern, String str) {
         String[] strs=str.split(" ");
         if (pattern.length()!=strs.length) {
-			return false;
-		}
+            return false;
+        }
         //正向匹配
         Map<String,String> m=new HashMap<String, String>();
         //反向匹配
         Map<String,String> n=new HashMap<String, String>();
         for (int i = 0; i < strs.length; i++) {
-			String p=pattern.substring(i,i+1);
-			if (m.get(p)==null) {
-				m.put(p, strs[i]);
-			}else if (!m.get(p).equals(strs[i])) {
-				return false;
-			}
-			if (n.get(strs[i])==null) {
-				n.put(strs[i], p);
-			}else if (!n.get(strs[i]).equals(p)) {
-				return false;
-			}
-		}
+            String p=pattern.substring(i,i+1);
+            if (m.get(p)==null) {
+                m.put(p, strs[i]);
+            }else if (!m.get(p).equals(strs[i])) {
+                return false;
+            }
+            if (n.get(strs[i])==null) {
+                n.put(strs[i], p);
+            }else if (!n.get(strs[i]).equals(p)) {
+                return false;
+            }
+        }
         return true;
     }
 }
\ No newline at end of file
diff --git a/java/295. Find Median from Data Stream.java b/java/295. Find Median from Data Stream.java
index a00beae..2bde8a8 100644
--- a/java/295. Find Median from Data Stream.java	
+++ b/java/295. Find Median from Data Stream.java	
@@ -23,9 +23,9 @@ public void addNum(int num) {
             if(list.get(e)<num){
                 list.add(e+1,num);
             }else if(list.get(s)>num){
-            	list.add(s,num);
+                list.add(s,num);
             }else{
-            	list.add(e,num);
+                list.add(e,num);
             }
         }
     }
diff --git a/java/299. Bulls and Cows.java b/java/299. Bulls and Cows.java
index 1a90f89..0ab319a 100644
--- a/java/299. Bulls and Cows.java	
+++ b/java/299. Bulls and Cows.java	
@@ -1,29 +1,29 @@
 public class Solution {
     public String getHint(String secret, String guess) {
-    	int length=secret.length();
-    	if (length==0) {
-			return "0A0B";
-		}
-    	char[] cs=secret.toCharArray();
-    	char[] cg=guess.toCharArray();
-    	boolean[] f=new boolean[length];
-    	int a=0;
-    	for (int i = 0; i < length; i++) {
-			boolean flag=cs[i]==cg[i];
-			f[i]=flag;
-			a+=flag?1:0;
-		}
-    	boolean[] g=new boolean[length];
-    	int b=0;
-    	for (int i = 0; i < length; i++) {
-			for (int j = 0; j < length; j++) {
-				if (i!=j&&!g[j]&&!f[i]&&!f[j]&&cg[i]==cs[j]) {
-					b++;
-					g[j]=true;
-					break;
-				}
-			}
-		}
-    	return a+"A"+b+"B";
+        int length=secret.length();
+        if (length==0) {
+            return "0A0B";
+        }
+        char[] cs=secret.toCharArray();
+        char[] cg=guess.toCharArray();
+        boolean[] f=new boolean[length];
+        int a=0;
+        for (int i = 0; i < length; i++) {
+            boolean flag=cs[i]==cg[i];
+            f[i]=flag;
+            a+=flag?1:0;
+        }
+        boolean[] g=new boolean[length];
+        int b=0;
+        for (int i = 0; i < length; i++) {
+            for (int j = 0; j < length; j++) {
+                if (i!=j&&!g[j]&&!f[i]&&!f[j]&&cg[i]==cs[j]) {
+                    b++;
+                    g[j]=true;
+                    break;
+                }
+            }
+        }
+        return a+"A"+b+"B";
     }
 }
\ No newline at end of file
diff --git a/java/300. Longest Increasing Subsequence.java b/java/300. Longest Increasing Subsequence.java
index b5fbc4d..cf90735 100644
--- a/java/300. Longest Increasing Subsequence.java	
+++ b/java/300. Longest Increasing Subsequence.java	
@@ -1,37 +1,37 @@
 public class Solution {
-	int[] ans;
-	int length=0;
+    int[] ans;
+    int length=0;
     public int lengthOfLIS(int[] nums) {
-    	ans=new int[nums.length];
-    	for (int i = 0; i < nums.length; i++) {
-			f(nums[i]);
-		}
-    	return length;
+        ans=new int[nums.length];
+        for (int i = 0; i < nums.length; i++) {
+            f(nums[i]);
+        }
+        return length;
     }
     public void f(int n){
-    	if (length==0||ans[length-1]<n) {
-			ans[length]=n;
-			length++;
-		}else {
-			int s=0;
-			int e=length-1;
-			int m=(s+e)/2;
-			while (e-s>1) {
-			    if(ans[m]==n){
-					return;
-				}
-				if (ans[m]>n) {
-					e=m;
-				}else {
-					s=m;
-				}
-				m=(s+e)/2;
-			}
-			if (ans[s]>n) {
-				ans[s]=n;
-			}else {
-				ans[e]=n;
-			}
-		}
+        if (length==0||ans[length-1]<n) {
+            ans[length]=n;
+            length++;
+        }else {
+            int s=0;
+            int e=length-1;
+            int m=(s+e)/2;
+            while (e-s>1) {
+                if(ans[m]==n){
+                    return;
+                }
+                if (ans[m]>n) {
+                    e=m;
+                }else {
+                    s=m;
+                }
+                m=(s+e)/2;
+            }
+            if (ans[s]>n) {
+                ans[s]=n;
+            }else {
+                ans[e]=n;
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/java/306. Additive Number.java b/java/306. Additive Number.java
index 401cf75..19e970d 100644
--- a/java/306. Additive Number.java	
+++ b/java/306. Additive Number.java	
@@ -3,80 +3,80 @@ public boolean isAdditiveNumber(String num) {
         int length=num.length();
         int l=Math.min(length, length*2/3+3);
         for (int i = 0; i < l-2; i++) {
-			String first=num.substring(0,i+1);
-			for (int j = i+1; j < l-1; j++) {
-				int f=i+1;
-				int s=j-i;
-				int t=length-j-1;
-				if (t>=s&&t>=f) {
-					String second=num.substring(i+1,j+1);
-					String third=num.substring(j+1,length);
-					if (f(first, second, third)) {
-						return true;
-					}
-				}
-			}
-		}
+            String first=num.substring(0,i+1);
+            for (int j = i+1; j < l-1; j++) {
+                int f=i+1;
+                int s=j-i;
+                int t=length-j-1;
+                if (t>=s&&t>=f) {
+                    String second=num.substring(i+1,j+1);
+                    String third=num.substring(j+1,length);
+                    if (f(first, second, third)) {
+                        return true;
+                    }
+                }
+            }
+        }
         return false;
     }
     public boolean f(String first,String second,String third){
-    	if (third.equals("")) {
-			return true;
-		}
-    	int f=first.length();
-    	int s=second.length();
-    	int t=third.length();
-    	if (t<s||t<f) {
-			return false;
-		}
-    	String sum=addString(first, second);
-    	if (sum.length()>t) {
-			return false;
-		}
-    	String test=third.substring(0,sum.length());
-    	if (sum.equals(test)) {
-			return f(second, sum, third.substring(sum.length(),t));
-		}
-    	return false;
+        if (third.equals("")) {
+            return true;
+        }
+        int f=first.length();
+        int s=second.length();
+        int t=third.length();
+        if (t<s||t<f) {
+            return false;
+        }
+        String sum=addString(first, second);
+        if (sum.length()>t) {
+            return false;
+        }
+        String test=third.substring(0,sum.length());
+        if (sum.equals(test)) {
+            return f(second, sum, third.substring(sum.length(),t));
+        }
+        return false;
     }
     public String addString(String sa,String sb){
-    	int al=sa.length();
-    	int bl=sb.length();
-    	if (al<bl) {
-			return  addString(sb, sa);
-		}
-    	char[] a=sa.toCharArray();
-    	char[] b=sb.toCharArray();
-    	int[] sum=new int[al];
-    	boolean flag=false;
-    	for (int i = 0; i < bl; i++) {
-			sum[al-i-1]=Integer.parseInt(""+b[bl-i-1])+Integer.parseInt(""+a[al-i-1])+(flag?1:0);
-			if (sum[al-i-1]>=10) {
-				sum[al-i-1]-=10;
-				flag=true;
-			}else{
-				flag=false;
-			}
-		}
-    	for (int i = 0; i < al-bl; i++) {
-			sum[i]=Integer.parseInt(""+a[i]);
-		}
-    	StringBuffer sbf=new StringBuffer();
-    	if (!flag||al==bl) {
-    		for (int i = 0; i < sum.length; i++) {
-    			sbf.append(String.valueOf(sum[i]));
-    		}
-    		if (flag) {
-				return "1"+sbf.toString();
-			}else {
-				return sbf.toString();
-			}
-		}else {
-			sum[al-bl-1]++;
-			for (int i = 0; i < sum.length; i++) {
-    			sbf.append(String.valueOf(sum[i]));
-    		}
-			return sbf.toString();
-		}
+        int al=sa.length();
+        int bl=sb.length();
+        if (al<bl) {
+            return  addString(sb, sa);
+        }
+        char[] a=sa.toCharArray();
+        char[] b=sb.toCharArray();
+        int[] sum=new int[al];
+        boolean flag=false;
+        for (int i = 0; i < bl; i++) {
+            sum[al-i-1]=Integer.parseInt(""+b[bl-i-1])+Integer.parseInt(""+a[al-i-1])+(flag?1:0);
+            if (sum[al-i-1]>=10) {
+                sum[al-i-1]-=10;
+                flag=true;
+            }else{
+                flag=false;
+            }
+        }
+        for (int i = 0; i < al-bl; i++) {
+            sum[i]=Integer.parseInt(""+a[i]);
+        }
+        StringBuffer sbf=new StringBuffer();
+        if (!flag||al==bl) {
+            for (int i = 0; i < sum.length; i++) {
+                sbf.append(String.valueOf(sum[i]));
+            }
+            if (flag) {
+                return "1"+sbf.toString();
+            }else {
+                return sbf.toString();
+            }
+        }else {
+            sum[al-bl-1]++;
+            for (int i = 0; i < sum.length; i++) {
+                sbf.append(String.valueOf(sum[i]));
+            }
+            return sbf.toString();
+        }
     }
 }
\ No newline at end of file
diff --git a/java/315. Count of Smaller Numbers After Self.java b/java/315. Count of Smaller Numbers After Self.java
index 9d356ef..39e416b 100644
--- a/java/315. Count of Smaller Numbers After Self.java	
+++ b/java/315. Count of Smaller Numbers After Self.java	
@@ -1,35 +1,35 @@
 public class Solution {
     public List<Integer> countSmaller(int[] nums) {
-    	List<Integer> list=new ArrayList<Integer>();
-    	int length=nums.length;
+        List<Integer> list=new ArrayList<Integer>();
+        int length=nums.length;
         if (length==0) {
-			return list;
-		}
+            return list;
+        }
         List<Integer> ars=new ArrayList<Integer>();
         ars.add(nums[length-1]);
         list.add(0);
         for (int i = length-2; i >=0; i--) {
-        	int test=nums[i];
-        	int end=ars.size()-1;
-			int start=0;
-			int mid=(start+end)/2;
-			while (end-start>1) {
-				if (test<=ars.get(mid)) {
-					end=mid;
-				}else {
-					start=mid;
-				}
-				mid=(start+end)/2;
-			}
-			int res=end+1;
-			if (test<=ars.get(start)) {
-				res=start;
-			}else if (test<=ars.get(end)) {
-				res=end;
-			}
-			ars.add(res,test);
-			list.add(0,res);
-		}
+            int test=nums[i];
+            int end=ars.size()-1;
+            int start=0;
+            int mid=(start+end)/2;
+            while (end-start>1) {
+                if (test<=ars.get(mid)) {
+                    end=mid;
+                }else {
+                    start=mid;
+                }
+                mid=(start+end)/2;
+            }
+            int res=end+1;
+            if (test<=ars.get(start)) {
+                res=start;
+            }else if (test<=ars.get(end)) {
+                res=end;
+            }
+            ars.add(res,test);
+            list.add(0,res);
+        }
         return list;
     }
 }
\ No newline at end of file
diff --git a/java/316. Remove Duplicate Letters.java b/java/316. Remove Duplicate Letters.java
index f9a401e..c68bdc8 100644
--- a/java/316. Remove Duplicate Letters.java	
+++ b/java/316. Remove Duplicate Letters.java	
@@ -1,63 +1,63 @@
 public class Solution {
-	List<List<Integer>> totalList=new ArrayList<List<Integer>>();
-	int index=-1;
+    List<List<Integer>> totalList=new ArrayList<List<Integer>>();
+    int index=-1;
     public String removeDuplicateLetters(String s) {
         if (s==null||s.length()==0) {
-			return "";
-		}
+            return "";
+        }
         char[] chars=s.toCharArray();
         for (int i = 0; i < 26; i++) {
-        	List<Integer> list=new ArrayList<Integer>();
-        	totalList.add(list);
-		}
+            List<Integer> list=new ArrayList<Integer>();
+            totalList.add(list);
+        }
         for (int i = 0; i < chars.length; i++) {
-			int k=chars[i]-97;
-			totalList.get(k).add(i);
-		}
+            int k=chars[i]-97;
+            totalList.get(k).add(i);
+        }
         int count=0;
         for (int i = 0; i < 26; i++) {
-			if (totalList.get(i).size()!=0) {
-				count++;
-			}
-		}
+            if (totalList.get(i).size()!=0) {
+                count++;
+            }
+        }
         char[] ans=new char[count];
         for (int i = 0; i < count; i++) {
-			ans[i]=f();
-		}
+            ans[i]=f();
+        }
         return String.valueOf(ans);
     }
     public char f(){
-    	int min=Integer.MAX_VALUE;
-    	for (int i = 0; i < 26; i++) {
-    		if (totalList.get(i).size()!=0) {
-				int k=totalList.get(i).get(totalList.get(i).size()-1);
-				if (k<min) {
-					min=k;
-				}
-			}
-		}
-    	for (int i = 0; i < 26; i++) {
-    		if (totalList.get(i).size()!=0) {
-    			int val=totalList.get(i).get(0);
-    			if (val<=min&&val>index) {
-    				totalList.set(i, new ArrayList<Integer>());
-    				index=val;
-    				for (int j = 0; j < 26; j++) {
-						if (totalList.get(j).size()!=0) {
-							List<Integer> list=totalList.get(j);
-							for (int k = 0; k < list.size();) {
-								if (list.get(0)<index) {
-									list.remove(0);
-								}else {
-									break;
-								}
-							}
-						}
-					}
-    				return (char)(i+97);
-    			}
-			}
-		}
-		return 0;
+        int min=Integer.MAX_VALUE;
+        for (int i = 0; i < 26; i++) {
+            if (totalList.get(i).size()!=0) {
+                int k=totalList.get(i).get(totalList.get(i).size()-1);
+                if (k<min) {
+                    min=k;
+                }
+            }
+        }
+        for (int i = 0; i < 26; i++) {
+            if (totalList.get(i).size()!=0) {
+                int val=totalList.get(i).get(0);
+                if (val<=min&&val>index) {
+                    totalList.set(i, new ArrayList<Integer>());
+                    index=val;
+                    for (int j = 0; j < 26; j++) {
+                        if (totalList.get(j).size()!=0) {
+                            List<Integer> list=totalList.get(j);
+                            for (int k = 0; k < list.size();) {
+                                if (list.get(0)<index) {
+                                    list.remove(0);
+                                }else {
+                                    break;
+                                }
+                            }
+                        }
+                    }
+                    return (char)(i+97);
+                }
+            }
+        }
+        return 0;
     }
 }
\ No newline at end of file
diff --git a/java/318. Maximum Product of Word Lengths.java b/java/318. Maximum Product of Word Lengths.java
index 231e4f1..ef544b1 100644
--- a/java/318. Maximum Product of Word Lengths.java	
+++ b/java/318. Maximum Product of Word Lengths.java	
@@ -1,61 +1,61 @@
-	Map<Character,Map<Integer,Integer>> map=new HashMap<Character, Map<Integer,Integer>>();
-	//装初始字符串数组
-	String[] initStrs=null;
-	//装处理过的字符串数组
-	String[] nowStrs=null;
+    Map<Character,Map<Integer,Integer>> map=new HashMap<Character, Map<Integer,Integer>>();
+    //装初始字符串数组
+    String[] initStrs=null;
+    //装处理过的字符串数组
+    String[] nowStrs=null;
     public int maxProduct(String[] words) {
-    	int length=words.length;
-    	if (length<2) {
-			return 0;
-		}
-    	initStrs=words;
-    	nowStrs=new String[length];
-    	Map<String,Integer> cond=null;
-    	StringBuffer sb=null;
-    	//对原数组进行处理，保证处理后的字符串中没有重复字母，缩减判断时间
-    	for (int i = 0; i < length; i++) {
-    		cond=new HashMap<String, Integer>();
-    		sb=new StringBuffer();
-    		for (int j = 0; j < words[i].length(); j++) {
-    			String k=words[i].substring(j,j+1);
-				if (cond.get(k)==null) {
-					sb.append(k);
-					cond.put(k,1);
-				}
-			}
-    		nowStrs[i]=sb.toString();
-		}
-    	//遍历原有数组，按字符写进map
-    	for (int i = 0; i < length; i++) {
-			char[] cs=nowStrs[i].toCharArray();
-			for (int j = 0; j < cs.length; j++) {
-				if (map.get(cs[j])==null) {
-					Map<Integer,Integer> m=new HashMap<Integer, Integer>();
-					m.put(i, 1);
-					map.put(cs[j], m);
-				}else {
-					map.get(cs[j]).put(i, 1);
-				}
-			}
-		}
-    	int max=0;
-    	for (int i = 0; i < length; i++) {
-			for (int j = i+1; j < length; j++) {
-				int test=f(i,j);
-				if (test>max) {
-					max=test;
-				}
-			}
-		}
-    	return max;
+        int length=words.length;
+        if (length<2) {
+            return 0;
+        }
+        initStrs=words;
+        nowStrs=new String[length];
+        Map<String,Integer> cond=null;
+        StringBuffer sb=null;
+        //对原数组进行处理，保证处理后的字符串中没有重复字母，缩减判断时间
+        for (int i = 0; i < length; i++) {
+            cond=new HashMap<String, Integer>();
+            sb=new StringBuffer();
+            for (int j = 0; j < words[i].length(); j++) {
+                String k=words[i].substring(j,j+1);
+                if (cond.get(k)==null) {
+                    sb.append(k);
+                    cond.put(k,1);
+                }
+            }
+            nowStrs[i]=sb.toString();
+        }
+        //遍历原有数组，按字符写进map
+        for (int i = 0; i < length; i++) {
+            char[] cs=nowStrs[i].toCharArray();
+            for (int j = 0; j < cs.length; j++) {
+                if (map.get(cs[j])==null) {
+                    Map<Integer,Integer> m=new HashMap<Integer, Integer>();
+                    m.put(i, 1);
+                    map.put(cs[j], m);
+                }else {
+                    map.get(cs[j]).put(i, 1);
+                }
+            }
+        }
+        int max=0;
+        for (int i = 0; i < length; i++) {
+            for (int j = i+1; j < length; j++) {
+                int test=f(i,j);
+                if (test>max) {
+                    max=test;
+                }
+            }
+        }
+        return max;
     }
     public int f(int i,int j){
-    	char[] csi=nowStrs[i].toCharArray();
-    	//选择一个字符串开始读取，如果该字符串包含的任意一个另外字符串拥有的字符，则返回0
-    	for (int k = 0; k < csi.length; k++) {
-			if (map.get(csi[k]).get(j)!=null) {
-				return 0;
-			}
-		}
-    	return initStrs[i].length()*initStrs[j].length();
+        char[] csi=nowStrs[i].toCharArray();
+        //选择一个字符串开始读取，如果该字符串包含的任意一个另外字符串拥有的字符，则返回0
+        for (int k = 0; k < csi.length; k++) {
+            if (map.get(csi[k]).get(j)!=null) {
+                return 0;
+            }
+        }
+        return initStrs[i].length()*initStrs[j].length();
     }
diff --git a/java/322. Coin Change.java b/java/322. Coin Change.java
index 5eda1a9..588c007 100644
--- a/java/322. Coin Change.java	
+++ b/java/322. Coin Change.java	
@@ -1,37 +1,37 @@
 public class Solution {
-	int[] array;
-	int minValue;
-	Map<Integer,Integer> map=new HashMap<Integer, Integer>();
+    int[] array;
+    int minValue;
+    Map<Integer,Integer> map=new HashMap<Integer, Integer>();
     public int coinChange(int[] coins, int amount) {
-    	Arrays.sort(coins);
-    	minValue=coins[0];
-    	array=coins;
-    	return f(amount);
+        Arrays.sort(coins);
+        minValue=coins[0];
+        array=coins;
+        return f(amount);
     }
     public int f(int amount){
-    	if (map.get(amount)!=null) {
-			return map.get(amount);
-		}
-    	if (amount==0) {
-			return 0;
-		}
-    	if (amount<minValue) {
-			return -1;
-		}
-    	int min=Integer.MAX_VALUE;
-    	for (int i = 0; i < array.length; i++) {
-			int v=f(amount-array[i]);
-			if (v!=-1&&v<min) {
-				min=v;
-			}
-		}
-    	int ans=0;
-    	if (min==Integer.MAX_VALUE) {
-			ans=-1;
-		}else{
-			ans=1+min;
-		}
-    	map.put(amount,ans);
-    	return ans;
+        if (map.get(amount)!=null) {
+            return map.get(amount);
+        }
+        if (amount==0) {
+            return 0;
+        }
+        if (amount<minValue) {
+            return -1;
+        }
+        int min=Integer.MAX_VALUE;
+        for (int i = 0; i < array.length; i++) {
+            int v=f(amount-array[i]);
+            if (v!=-1&&v<min) {
+                min=v;
+            }
+        }
+        int ans=0;
+        if (min==Integer.MAX_VALUE) {
+            ans=-1;
+        }else{
+            ans=1+min;
+        }
+        map.put(amount,ans);
+        return ans;
     }
 }
\ No newline at end of file
diff --git a/java/328. Odd Even Linked List.java b/java/328. Odd Even Linked List.java
index d01f8c5..c81a7c4 100644
--- a/java/328. Odd Even Linked List.java	
+++ b/java/328. Odd Even Linked List.java	
@@ -9,7 +9,7 @@
 public class Solution {
     public ListNode oddEvenList(ListNode head) {
         if(head==null||head.next==null){
-        	return head;
+            return head;
         }
         ListNode odd=head;
         ListNode even=head.next;
@@ -19,16 +19,16 @@ public ListNode oddEvenList(ListNode head) {
         head=head.next.next;
         int i=1;
         while (head!=null) {
-        	if (i%2==0) {
-        		even.next=head;
-				even=even.next;
-			}else {
-				odd.next=head;
-        		odd=odd.next;
-			}
-			head=head.next;
-			i++;
-		}
+            if (i%2==0) {
+                even.next=head;
+                even=even.next;
+            }else {
+                odd.next=head;
+                odd=odd.next;
+            }
+            head=head.next;
+            i++;
+        }
         even.next=null;
         odd.next=evenStart;
         return oddStart;
diff --git a/java/329. Longest Increasing Path in a Matrix.java b/java/329. Longest Increasing Path in a Matrix.java
index e28e781..f1e0f85 100644
--- a/java/329. Longest Increasing Path in a Matrix.java	
+++ b/java/329. Longest Increasing Path in a Matrix.java	
@@ -1,13 +1,13 @@
 public class Solution {
-	boolean[][] flag=null;
-	int[][] nums=null;
-	int[][] ans=null;
-	int rows=0;
-	int cols=0;
+    boolean[][] flag=null;
+    int[][] nums=null;
+    int[][] ans=null;
+    int rows=0;
+    int cols=0;
     public int longestIncreasingPath(int[][] matrix) {
         rows=matrix.length;
         if(rows==0){
-        	return 0;
+            return 0;
         }
         cols=matrix[0].length;
         flag=new boolean[rows][cols];
@@ -15,39 +15,39 @@ public int longestIncreasingPath(int[][] matrix) {
         ans=new int[rows][cols];
         int res=1;
         for (int i = 0; i < rows; i++) {
-			for (int j = 0; j < cols; j++) {
-				if ((i>0&&matrix[i-1][j]>matrix[i][j])||(j>0&&matrix[i][j-1]>matrix[i][j])||(i<rows-1&&matrix[i+1][j]>matrix[i][j])||(j<cols-1&&matrix[i][j+1]>matrix[i][j])) {
-					int test=f(i, j,0);
-					if (test>res) {
-						res=test;
-					}
-				}
-			}
-		}
+            for (int j = 0; j < cols; j++) {
+                if ((i>0&&matrix[i-1][j]>matrix[i][j])||(j>0&&matrix[i][j-1]>matrix[i][j])||(i<rows-1&&matrix[i+1][j]>matrix[i][j])||(j<cols-1&&matrix[i][j+1]>matrix[i][j])) {
+                    int test=f(i, j,0);
+                    if (test>res) {
+                        res=test;
+                    }
+                }
+            }
+        }
         return res;
     }
     public int f(int x,int y,int d){
-    	int nx=x+(d%2);
-    	int ny=y+(d/2);
-    	if(nx<0||nx>=rows||ny<0||ny>=cols){
-    		return 0;
-    	}else if (d!=0&&nums[nx][ny]<=nums[x][y]) {
-			return 0;
-		}else if(flag[nx][ny]){
-			return ans[nx][ny];
-		} else {
-			int res=0;
-			for (int i = -2; i <=2; i++) {
-				if (i!=0) {
-					int test=f(nx,ny,i);
-					if (test>res) {
-						res=test;
-					}
-				}
-			}
-			flag[nx][ny]=true;
-			ans[nx][ny]=res+1;
-			return res+1;
-		}
+        int nx=x+(d%2);
+        int ny=y+(d/2);
+        if(nx<0||nx>=rows||ny<0||ny>=cols){
+            return 0;
+        }else if (d!=0&&nums[nx][ny]<=nums[x][y]) {
+            return 0;
+        }else if(flag[nx][ny]){
+            return ans[nx][ny];
+        } else {
+            int res=0;
+            for (int i = -2; i <=2; i++) {
+                if (i!=0) {
+                    int test=f(nx,ny,i);
+                    if (test>res) {
+                        res=test;
+                    }
+                }
+            }
+            flag[nx][ny]=true;
+            ans[nx][ny]=res+1;
+            return res+1;
+        }
     }
 }
\ No newline at end of file
diff --git a/java/331. Verify Preorder Serialization of a Binary Tree.java b/java/331. Verify Preorder Serialization of a Binary Tree.java
index b3fb49d..f1a926e 100644
--- a/java/331. Verify Preorder Serialization of a Binary Tree.java	
+++ b/java/331. Verify Preorder Serialization of a Binary Tree.java	
@@ -1,30 +1,30 @@
 public class Solution {
     public boolean isValidSerialization(String preorder) {
-    	String[] strs=preorder.split(",");
-    	List<String> list=new ArrayList<String>();
-    	for (int i = 0; i < strs.length; i++) {
-			list.add(strs[i]);
-		}
-    	return isValid(list);
+        String[] strs=preorder.split(",");
+        List<String> list=new ArrayList<String>();
+        for (int i = 0; i < strs.length; i++) {
+            list.add(strs[i]);
+        }
+        return isValid(list);
     }
     public boolean isValid(List<String> list) {
-    	int len=list.size();
-    	if (len==1) {
-			return "#".equals(list.get(0));
-		}
-    	for (int i = 0; i < len-2; i++) {
-			if ("#".equals(list.get(i+1))&&"#".equals(list.get(i+2))) {
-				if ("#".equals(list.get(i))) {
-					return false;
-				}else{
-					list.remove(i+2);
-					list.remove(i+1);
-					list.remove(i);
-					list.add(i,"#");
-					return isValid(list);
-				}
-			}
-		}
-    	return false;
+        int len=list.size();
+        if (len==1) {
+            return "#".equals(list.get(0));
+        }
+        for (int i = 0; i < len-2; i++) {
+            if ("#".equals(list.get(i+1))&&"#".equals(list.get(i+2))) {
+                if ("#".equals(list.get(i))) {
+                    return false;
+                }else{
+                    list.remove(i+2);
+                    list.remove(i+1);
+                    list.remove(i);
+                    list.add(i,"#");
+                    return isValid(list);
+                }
+            }
+        }
+        return false;
     }
 }
\ No newline at end of file
diff --git a/java/341. Flatten Nested List Iterator.java b/java/341. Flatten Nested List Iterator.java
index ad19328..6b03414 100644
--- a/java/341. Flatten Nested List Iterator.java	
+++ b/java/341. Flatten Nested List Iterator.java	
@@ -17,9 +17,9 @@
  */
 public class NestedIterator implements Iterator<Integer> {
     private List<Integer> ans;
-	private int index;
-	private int length;
-	
+    private int index;
+    private int length;
+    
     public NestedIterator(List<NestedInteger> nestedList) {
         ans=init(nestedList);
         index=0;
@@ -28,24 +28,24 @@ public NestedIterator(List<NestedInteger> nestedList) {
 
     @Override
     public Integer next() {
-		return index<length?ans.get(index++):null;
+        return index<length?ans.get(index++):null;
     }
 
     @Override
     public boolean hasNext() {
-		return index<length;
+        return index<length;
     }
     
     public List<Integer> init(List<NestedInteger> nestedList){
-    	List<Integer> list=new ArrayList<Integer>();
-    	for (NestedInteger nestedInteger : nestedList) {
-			if (nestedInteger.isInteger()) {
-				list.add(nestedInteger.getInteger());
-			}else{
-				list.addAll(init(nestedInteger.getList()));
-			}
-		}
-    	return list;
+        List<Integer> list=new ArrayList<Integer>();
+        for (NestedInteger nestedInteger : nestedList) {
+            if (nestedInteger.isInteger()) {
+                list.add(nestedInteger.getInteger());
+            }else{
+                list.addAll(init(nestedInteger.getList()));
+            }
+        }
+        return list;
     }
 }
 
diff --git a/java/343. Integer Break.java b/java/343. Integer Break.java
index 78d24c6..d68c3be 100644
--- a/java/343. Integer Break.java	
+++ b/java/343. Integer Break.java	
@@ -1,29 +1,29 @@
 public class Solution {
-	Map<Integer, Integer> map = new HashMap<Integer, Integer>() {
-		{
-			put(2, 2);
-			put(3, 3);
-		}
-	};
-	public int integerBreak(int n) {
-		if (n == 2)
-			return 1;
-		if (n == 3)
-			return 2;
-		return f(n);
-	}
+    Map<Integer, Integer> map = new HashMap<Integer, Integer>() {
+        {
+            put(2, 2);
+            put(3, 3);
+        }
+    };
+    public int integerBreak(int n) {
+        if (n == 2)
+            return 1;
+        if (n == 3)
+            return 2;
+        return f(n);
+    }
 
-	public int f(int n) {
-		if (map.get(n) == null) {
-			int sum = 0;
-			for (int i = 2; i < n - 1; i++) {
-				int test = f(i) * f(n - i);
-				if (test > sum) {
-					sum = test;
-				}
-			}
-			map.put(n, sum);
-		}
-		return map.get(n);
-	}
+    public int f(int n) {
+        if (map.get(n) == null) {
+            int sum = 0;
+            for (int i = 2; i < n - 1; i++) {
+                int test = f(i) * f(n - i);
+                if (test > sum) {
+                    sum = test;
+                }
+            }
+            map.put(n, sum);
+        }
+        return map.get(n);
+    }
 }
\ No newline at end of file
diff --git a/java/345. Reverse Vowels of a String.java b/java/345. Reverse Vowels of a String.java
index ffe4dce..c8fff4f 100644
--- a/java/345. Reverse Vowels of a String.java	
+++ b/java/345. Reverse Vowels of a String.java	
@@ -4,20 +4,20 @@ public String reverseVowels(String s) {
         int i=0;
         int j=cs.length-1;
         while (i<j) {
-			while (i<j&&cs[i]!=65&&cs[i]!=69&&cs[i]!=73&&cs[i]!=79&&cs[i]!=85&&cs[i]!=97&&cs[i]!=101&&cs[i]!=105&&cs[i]!=111&&cs[i]!=117) {
-				i++;
-			}
-			while (i<j&&cs[j]!=65&&cs[j]!=69&&cs[j]!=73&&cs[j]!=79&&cs[j]!=85&&cs[j]!=97&&cs[j]!=101&&cs[j]!=105&&cs[j]!=111&&cs[j]!=117) {
-				j--;
-			}
-			if (i<j) {
-				char c=cs[i];
-				cs[i]=cs[j];
-				cs[j]=c;
-				i++;
-				j--;
-			}
-		}
+            while (i<j&&cs[i]!=65&&cs[i]!=69&&cs[i]!=73&&cs[i]!=79&&cs[i]!=85&&cs[i]!=97&&cs[i]!=101&&cs[i]!=105&&cs[i]!=111&&cs[i]!=117) {
+                i++;
+            }
+            while (i<j&&cs[j]!=65&&cs[j]!=69&&cs[j]!=73&&cs[j]!=79&&cs[j]!=85&&cs[j]!=97&&cs[j]!=101&&cs[j]!=105&&cs[j]!=111&&cs[j]!=117) {
+                j--;
+            }
+            if (i<j) {
+                char c=cs[i];
+                cs[i]=cs[j];
+                cs[j]=c;
+                i++;
+                j--;
+            }
+        }
         return String.valueOf(cs);
     }
 }
\ No newline at end of file