剑指Offer-48 最长不含重复字符的子字符串

题目：

请从字符串中找出一个最长的不包含重复字符的子字符串，计算该最长子字符串的长度。假设字符串中只包含从’a’到’z’的字符。
样例
输入：“abcabc”
输出：3

解答：

class Solution:
	def longestSubstringWithoutDuplication(self, s):
		"""
		:type s: str
		:rtype: int
		"""
		d = {}
		maxLength, start, curLength = 0, 0, 0
		for i in range(len(s)):
			if s[i] not in d:
				d[s[i]] = i
				curLength += 1
			else:
				for j in range(start, d[s[i]]):
					del d[s[j]]
				start = d[s[i]] + 1
				d[s[i]] = i
				maxLength = max(maxLength, curLength)
				curLength = i - start + 1
		maxLength = max(maxLength, curLength)
		return maxLength