面试题：找出数组中只出现一次的数字

public class Solution {
public int singleNumber(int[] nums) {
int n =0;

// as we know that bitwise XOR in Java
// 0 ^ N = N
// N ^ N = 0
for(int i=0; i!=nums.length; i++) {
n ^= nums[i];
}

return n;
}
}