2 ways of solving "Longest Substring Without Repeating Characters" problem in JavaScript

longestSubstringWithoutRepeatingCharacters.js

//SLIDING WINDOW METHOD
var lengthOfLongestSubstring = function(s) {
    
    let count = 0;

    let i = 0;
    let j = 0;
    let end = s.length;
    let set = new Set();

    while (i < end && j < end) {
        let char = s.charAt(j);
        if(!set.has(char)) {
            set.add(char);
            j++;
            count = Math.max (count, j - i);
        } else {
            set.delete(s.charAt(i));
            i++;
        }
    }

    return count;
};

let result = lengthOfLongestSubstring('abcabcbb')
console.log(result);