正整数的二进制表示有多少个1

#include <iostream>
using namespace std;

typedef unsigned int u32;

u32 CountOneOfNum(u32 num)
{
    if (0 == num)
    {
        return 0;
    }

    u32 nCnt = 1;
    while( (num&(num-1)) != 0)
    {
        nCnt++;
        num = (num&(num-1));
    }

    return nCnt;
}

int main()
{
    std::cout << CountOneOfNum(8) << std::endl;
    std::cout << CountOneOfNum(14) << std::endl;

    return 0;
}