[LeetCode] [Single Number 2013-10-01]

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?

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