函数式leetcode-3

class Solution(object):    def lengthOfLongestSubstring(self, s):        """        :type s: str        :rtype: int        """        max = 0        myStr = ''        for char in s:            index = myStr.find(char)            if index == -1:                myStr+=char            else :                if len(myStr) > max:                    max = len(myStr)                myStr = myStr[index + 1:] + char        if len(myStr) > max:            max = len(myStr)        return maxif __name__ == '__main__':    test = Solution()    print(test.lengthOfLongestSubstring('pwwkew '))