lintcode->落单的数

package 落单的数;

public class Solution {

public int singleNumber(int[] A) {
// Write your code here
int ans = 0;
for(int i:A){
ans ^= i;
}
return ans;
}
public static void main(String[] args) {
int[] A = {1,2,3,1,2};
System.out.println(new Solution().singleNumber(A));
}

}