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?
cpp代码如下:
class Solution {
public:
int singleNumber(int A[], int n) {
int ans=0;
for(int i=0;i<n;++i){
ans^=A[i];
}
return ans;
}
};