学步园

Single Number（Java代码）

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?

解题思路：利用异或，定义一个为0的变量，和数组中每一个数异或，得到只出现一次的数。

public class Solution {
	public int singleNumber(int[] A) {
		int number = 0;
		for (int i = 0; i < A.length; i++) {
			number = number ^ A[i];
		}
		return number;
	}
}