Leetcode刷题第003天

一、只出现一次的数字

 1 class Solution {
 2 public:
 3     int singleNumber(vector<int>& nums) 
 4     {
 5         int res = 0;
 6         for (auto num : nums) 
 7             res ^= num;
 8         return res;
 9     }
10 };