LCS without Repetation

Author: spdpiyush

LeetCode/String/LongestSubStringWithoutRepetation.java

@@ -0,0 +1,39 @@
+/**
+ * @author : Piyush Kumar
+ * Problem Link : https://leetcode.com/problems/longest-substring-without-repeating-characters/
+ */
+
+class Solution {
+    public int lengthOfLongestSubstring(String s) {
+        char[] ch = s.toCharArray();
+        Map<Character, Integer> map = new HashMap<>();
+        int max = ch.length==0 ? 0 : 1;
+        int count = 1;
+        for (int i=0, j=0; i < ch.length - 1; ) {
+            map.put(ch[i], 1);
+            if (max == ch.length) {
+                break;
+            }
+            if (ch[j] != ch[j+1]  && !map.containsKey(ch[j+1])) {
+                map.put(ch[j+1], 1);
+                j++;
+                count++;
+                if (count > max) {
+                    max = count;
+                }
+                if (j == (ch.length - 1)) {
+                    i++;
+                    j=i;
+                    count=1;
+                }
+            }else {
+                map.clear();
+                i++;
+                j = i;
+                count = 1;
+            }
+        }
+        return max;
+    }
+}
+