136. Single Number

Given an array of integers, every element appears twice except for one. Find that single one.

//只有一个元素不一样。那么集合中所有元素异或就可以得到结果。

class Solution {
public:
    int singleNumber(vector<int>& nums) {
        int res = 0;
        for(int i = 0;i<nums.size();i++){
            res ^= nums[i];
        }
        return res;
    }
};