LeetCode 136. Single Number

题目

Given an array of integers, every element appears twice except for one. Find that single one.
Note:
Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?

思路

所有数字异或，得到的最后的数字就是所求。

代码

class Solution:
    def singleNumber(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        result = 0
        for num in nums:
            result ^= num
        return result