Leetcode-single Number

#Leetcode

题目描述

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?

代码

	class Solution {
			public:
			    int singleNumber(int A[], int n) {
				// IMPORTANT: Please reset any member data you declared, as
				// the same Solution instance will be reused for each test case.
				if(A == NULL || n == 0)
				    return 0;
				int result = A[0];
				for(int i = 1; i < n; i++)
				    result = result ^ A[i];
				return result;
			    }
			};