#3 longest-substring-without-repeating-characters

最长不重复子串：

The firt coding;
Using list

class Solution(object):
    def lengthOfLongestSubstring(self, s):
        """
        :type s: str
        :rtype: int
        """
        arr = []
        n = 0
        for str in s :
            if(str in arr) :
                if(len(arr)>n) :
                    n = len(arr)
                arr = arr[arr.index(str)+1:]
            arr.append(str)
        if(len(arr) > n):
            n = len(arr)
        return n

Runtime: 156 ms

The Second coding :
Using dict {}

class Solution(object):
    def lengthOfLongestSubstring(self, s):
        """
        :type s: str
        :rtype: int
        """
        arr = {}
        n,i,j = 0,0,0
        for str in s :
            if(str in arr) :
                n = max(j-i,n)
                i = max(arr[str], i)
            j+=1
            arr[str] = j
        n = max(j-i,n)
        return n

Runtime: 116 ms