Longest Substring Without Repeating Charactersmedium

import java.util.*;

public class Main {
    public static int lengthOfLongestSubstring(String s) {
        // TODO: sliding window with a HashMap
        return 0;
    }

    public static void main(String[] args) {
        System.out.println(lengthOfLongestSubstring("abcabcbb")); // 3
        System.out.println(lengthOfLongestSubstring("bbbbb"));    // 1
        System.out.println(lengthOfLongestSubstring("pwwkew"));   // 3
    }
}