136 Single Number(找唯一数Medium)

题目意思：一个int数组，有一个数只出现一次，其他数均出现两次，找到这个唯一数

知识普及：~：非运算，单目运算符1为0,0为1;

　　　　 &：与运算，都为1则为1，否则为0

　　　　　|：或运算，全为0则为0，否则为1

　　 ^：异或运算，相同为0，不同为1

思路：将数组中元素进行异或运算，则只剩下0和唯一数，异或得到的是唯一数

 1 class Solution {
 2 public:
 3     int singleNumber(vector<int>& nums) {
 4         int res=0;
 5         for(int i=0;i<nums.size();++i){
 6             res^=nums[i];
 7         }
 8         return res;
 9     }
10 };

时间复杂度:O(n)

时间： 2024-10-25 11:26:21

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