[Leetcode] Single Number

Single Number

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?

Algorithm: Using XOR, since XOR will return 1 if the two integers are different, and 0 if they're same.
Solution in C++

class Solution {
public:
    int singleNumber(int A[], int n) {
        int x=0;
        for(int i=0;i<n;i++)
        {
            x=x^A[i];
        }
        return x;
    }
};