LeetCode-136. Single Number

Given a non-empty 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?

Example 1:

Input: [2,2,1]
Output: 1

Example 2:

Input: [4,1,2,1,2]
Output: 4

public int singleNumber(int[] nums) {//位运算 异或
        int re =nums[0];
        for (int i = 1; i < nums.length; i++) {
            re = re^nums[i];
        }
        return re;
    }