Leetcode 3: Longest Substring Without Repeating Characters

 1 public class Solution {
 2     public int LengthOfLongestSubstring(string s) {
 3         int i = 0, j = 0, curMax = 0;
 4         
 5         var dict = new Dictionary<char, int>();
 6         
 7         while (j < s.Length)
 8         {
 9             if (dict.ContainsKey(s[j]))
10             {
11                 var index = dict[s[j]];
12                 while (i <= index)
13                 {
14                     dict.Remove(s[i]);
15                     i++;
16                 }                            
17             }
18             else
19             {
20                 curMax = Math.Max(curMax, j - i + 1);
21             }
22             
23             dict[s[j]] = j;
24             j++;
25         }
26         
27         return curMax;
28     }
29 }