Given a non-empty 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?
Example 1:
Input: [2,2,1]
Output: 1
Example 2:
Input: [4,1,2,1,2]
Output: 4
class Solution {
public:
int singleNumber(vector<int>& nums) {
int a = nums[];
for(int i = ; i < nums.size();i++)
a^=nums[i];
return a;
}
};