date: 2018/09/19 原文
1. Question
Given a non-empty array of integers, every element appears twice except for one. Find that single one.
Example 1:
Input: [2,2,1]
Output: 1
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Example 2:
Input: [4,1,2,1,2]
Output: 4
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2. Solution
class Solution {
public int singleNumber(int[] nums) {
int i = 1;
int a = nums[0];
while (i < nums.length) {
a = a ^ nums[i]; //利用与或的关系
i++;
}
return a;
}
}
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3. Think
思路: 利用java中与或关系,进行运算最优