编辑代码

const str = 'qweqtyuiopasdfqhjk';

function findMaxLength (s) {
    let l= 0, total =0;
    let res = 0;
    let cur = {}
    for(r in s) {
        res = Math.max(r - l + 1, res);
        if(cur[s[r]]) {
            res -= 1;
            l = r;
        }else {
            cur[s[r]] = 1;
        }
    }
    return res
}

console.log(findMaxLength(str))