Longest_Sub_String_without_Repeat_Characters_Sliding

Longest_Sub_String_without_Repeat_Characters_Sliding.cpp

class Solution {
public:
    int lengthOfLongestSubstring(string s) {
        unordered_map<char, int> set;
        int n = s.size();
        int i=0, j=0, maxLength = 0;
        while(i<n&&j<n)
        {
            if(set.find(s[j])!=set.end())
            {
                i = max(i,set[s[j]]);
                set.erase(s[j]);
            }
            else
            {
                set[s[j]] = j + 1;
                maxLength = max(maxLength, j-i+1);
                j++;
            }
        }
        return maxLength;
    }
};