Single Number II 每个数出现3次，求单个数

Single Number II

Given an array of integers, every element appears three

Note:
Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?

class Solution {
public:
//出现3次，每位都3次，对3取余为0，,剩余的就是那个单独的数
    int singleNumber(vector<int>& nums) {
        
        int one=0,two=0,three=0;
        for(int i=0;i<nums.size();i++)
        {
            two|=one&nums[i];
            one^=nums[i];
            three=(one&two);
            one&= ~three;//三次清0
            two&= ~three;
        }
        return one;
    }
};