找到单独的数字 Single Number

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?

class Solution {
public:
    int singleNumber(int A[], int n) {
        for(int i = 1; i < n; ++i){
		   A[0] ^= A[i];
	    }
	    return A[0];
    }
};

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找到单独的数字 Single Number

原文：http://blog.csdn.net/fox64194167/article/details/18798135