[算法学习][leetcode] 191 Number of 1 Bits

https://leetcode.com/problems/number-of-1-bits/description/

题目

Write a function that takes an unsigned integer and returns the number of ’1’ bits it has (also known as the Hamming weight).

For example, the 32-bit integer ’11’ has binary representation 00000000000000000000000000001011, so the function should return 3.

题目翻译

题目解析

求一个数的二进制中有多少个1。

参考答案

class Solution {
public:
    int hammingWeight(uint32_t n) {
        if(0==n) {
            return 0;
        }
        int iCount = 1;
        while (n = n & (n-1))
        {
            iCount++;
        }
        return iCount;
    }
};