simple rough direct code
is easy to understand with console, the code is as follows:
var lengthOfLongestSubstring = function (s) {
var arr = [];
var max = 0;
for (let index = 0; index < s.length; index++) {
var a = arr.indexOf(s[index]);
console.log(a, s[index], 222)
if (a != -1) {
arr.splice(0, a + 1)
console.log(111, arr, max)
}
arr.push(s.charAt(index))
console.log(arr, 222)
max = Math.max(arr.length, max)
}
return console.log(max, arr)
};
lengthOfLongestSubstring('abcdeasasas')
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