longest substring without repeating characters python solution

Author: lazybing

python/leetcode3_longest_substring_without_repeating_characters/solution.py

@@ -40,3 +40,19 @@ def lengthOfLongestSubstring(self, s:str)->int:
             right = right + 1
 
         return res
+
+# runtime 72ms beat 56%
+class Solution:
+    def lengthOfLongestSubstring(self, s:str)->int:
+        res, left, right = 0, 0, 0
+        dic = {}
+
+        while right < len(s) and left + res < len(s):
+            if s[right] in dic:
+                left = max(left, dic[s[right]] + 1)
+
+            dic[s[right]] = right
+            res = max(res, right - left + 1)
+            right = right + 1
+
+        return res