lengthOfLongestSubstring.cpp

int lengthOfLongestSubstring(string s) {
         set<char> cache;
        int m = 0;
         int count = 0;
        for(int i = 0; i < s.size(); i++){
            cache.clear();
            
            cache.insert(s[i]);
            count = 1;
            for(int j = i + 1; j < s.size(); j++){
                if(cache.insert(s[j]).second!= true){
                    break;
                }else{
                    count++;
                }
            }
          m = max(m, count); 
        }
        return m;
    }