LeetCode -- Single Number

Question:

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?

Analysis:

问题描述：给出一组数据，除只有一个数字出现1次外，每个数字出现两次。找出只出现一次的数字。

注意：你的算法应该在线性时间内运行，且不使用额外的空间。

Answer：

public class Solution {
    public int singleNumber(int[] nums) {
        if(nums == null || nums.length == 0)
            return 0;

        int result = 0;
        for(int i=0; i<nums.length; i++) {
            result = result ^ nums[i];
        }
        return result;
    }
}