最长无重复子数组

#
# 
# @param arr int整型一维数组 the array
# @return int整型

#
class Solution:
    def maxLength(self , arr ):
        # write code here
        n = len(arr)
        if n <= 1:
            return n
        hashMap = {}
        lo, hi = 0, 0
        res = 0
        while hi < n:
            curr = arr[hi]
            if curr not in hashMap:
                hashMap[curr] = 1

            else:
                while hashMap.has_key(curr) and lo<=hi:
                    del hashMap[arr[lo]]
                    lo += 1
                hashMap[curr] = 1
            res = max(res, hi-lo+1)
            hi += 1
        return res