268. Missing Number

Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.

给n个不同的数，求0-n这n+1个数里缺了哪个

利用异或运算的性质，可以on处理

class Solution(object):
    def missingNumber(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        ans = 0
        for i in range(1, len(nums) + 1):
            ans ^= i
        for value in nums:
            ans ^= value
        return ans