#include <iostream>

#include <string>

using namespace std;

class Solution {

public:

int lengthOfLongestSubstring(string s) {

if (s.empty()) {

return 0;

}

int max_sub = 1;

int left = 0;

int right = 0;

string sub_str = s.substr(left, right - left + 1);

while (right < s.size()) {

if (sub_str.find(s[right]) == (sub_str.size() - 1)) {

max_sub = max(max_sub, right - left + 1);

right++;

} else {

left++;

}

sub_str = s.substr(left, right - left + 1);

}

return max_sub;

}

};

int main() {

string str{""};

Solution solu;

cout << "result: " << solu.lengthOfLongestSubstring(str) << endl;

// cout << "try: " << str[0] << str[1] << str.find(str[0])<< endl;

return 0;

}