update

mitcc · Nov 27, 2013 · cb905c9 · cb905c9
1 parent fcac6d0
commit cb905c9
Showing 1 changed file with 33 additions and 44 deletions.
diff --git a/leetcode/MergeTwoSortedLists.java b/leetcode/MergeTwoSortedLists.java
@@ -13,50 +13,39 @@
  *     }
  * }
  */
-package info.mitcc.leetcode;
-
 public class MergeTwoSortedLists {
-	public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
-		if(l1 == null)
-			return l2;
-		if(l2 == null)
-			return l1;
-		if(l1.val < l2.val) {
-			l1.next = mergeTwoLists(l1.next, l2);
-			return l1;
-		} else {
-			l2.next = mergeTwoLists(l1, l2.next);
-			return l2;
-		}
-
-/*		ListNode result;
-		if(l1.val < l2.val) {
-			result = l1;
-			result.next = mergeTwoLists(l1.next, l2);
-		} else {
-			result = l2;
-			result.next = mergeTwoLists(l1, l2.next);
-		}
-		return result;*/
-	}
+    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
+        if(l1 == null)
+            return l2;
+        else if(l2 == null)
+            return l1;
+        else if(l1.val <= l2.val) {
+            l1.next = mergeTwoLists(l1.next, l2);
+            return l1;
+        } else {
+            l2.next = mergeTwoLists(l1, l2.next);
+            return l2;
+        }
+    }
 
-/*	public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
-		ListNode result = new ListNode(0);
-    	ListNode temp = result;
-		while(l1 != null & l2 != null) {
-			if(l1.val < l2.val) {
-				temp.next = l1;
-				l1 = l1.next;
-			} else {
-				temp.next = l2;
-				l2 = l2.next;
-			}
-			temp = temp.next;
-		}
-		if(l1 != null)
-			temp.next = l1;
-		if(l2 != null)
-			temp.next = l2;
-		return result.next;
-	}*/
+/*************************************************************/
+
+    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
+        ListNode res = new ListNode(0), cur = res;
+        while(l1 != null && l2 != null) {
+            if(l1.val < l2.val) {
+                cur.next = l1;
+                l1 = l1.next;
+            } else {
+                cur.next = l2;
+                l2 = l2.next;
+            }
+            cur = cur.next;
+        }
+        if(l1 == null) 
+            cur.next = l2;
+        else if(l2 == null)
+            cur.next = l1;
+        return res.next;
+    }
 }