【easy】268. Missing Number

Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.

Example 1

Input: [3,0,1]
Output: 2

Example 2

Input: [9,6,4,2,3,5,7,0,1]
Output: 8

用异或的办法：
class Solution {
public:
    int missingNumber(vector<int>& nums) {
        int len = nums.size();
        if(len == 0)
            return 0;
        int x = 0;
        for (int i=1;i<=len;i++)
            x ^= i;
        for (int i=0;i<len;i++)
            x ^= nums[i];
        return x;
    }
};



原文地址：https://www.cnblogs.com/sherry-yang/p/8454616.html
				


				
时间： 2024-11-13 09:03:59 

		


		


	

	
	

		


		
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