[leetcode-137-Single Number II]

Posted 2020-09-04 hellowOOOrld

Given an array of integers, every element appears three times except for one, which appears exactly once. Find that single one.

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

思路：

没有。。。看参考吧。。。。

int singleNumber(vector<int>& nums)
    {
        int result = 0;
        for (int i = 0; i < 32;i++)
        {
            int count = 0, bit = 1 << i;
            for (int j = 0; j < nums.size();j++)
            {
                if (nums[j] & bit) count++;            
            }
            if (count % 3 !=0)
                result |= bit;            
        }
        return result;
    }

 

参考：

http://www.cnblogs.com/higerzhang/p/4159330.html