leetcode-3无重复字符的最长字符串

class Solution:
    def lengthOfLongestSubstring(self, s: str) -> int:
        lst = list(s)
        maxl = 0
        sublst = []
        for i in lst:
            if i in sublst:
                pos = sublst.index(i)
                sublst = sublst[pos+1:]
                sublst.append(i)
            else:
                sublst.append(i)
                maxl = max(len(sublst),maxl)
        return maxl