Hash algorithm

Leetcode 3. Longest Substring Without Repeating Characters

Hint: use "Slicing Window"

class Solution(object):
    def lengthOfLongestSubstring(self, s):
        """
        :type s: str
        :rtype: int
        """
        if len(s) == 0:
            return 0

        substring = ""
        maxLen = 0

        for i in range(len(s)):
            if s[i] in substring:
                substring = substring[substring.index(s[i])+1:]

            substring += s[i]
            if maxLen < len(substring):
                maxLen = len(substring)

        return maxLen