Longest Substring Without Repeating Charactersmedium

#include <iostream>
#include <string>
#include <unordered_map>
using namespace std;

int lengthOfLongestSubstring(string s) {
    // TODO: sliding window with a map
    return 0;
}

int main() {
    cout << lengthOfLongestSubstring("abcabcbb") << endl; // 3
    cout << lengthOfLongestSubstring("bbbbb")    << endl; // 1
    cout << lengthOfLongestSubstring("pwwkew")   << endl; // 3
    return 0;
}