0710编程之美二进制树中1的个数 三种解法

#include<iostream>
using namespace std;
int main7101()//解法1
{
int a;
while (cin >> a)
{
int count = 0;
while (a)
{
if (a % 2 == 1)
count++;
a = a / 2;
}
cout << count << endl;
}
cin.get();
return 0;
}
int main7102()
{
int a;
while (cin >> a)
{
int count = 0;
while (a)
{
count += a & 0x01;
a = a >> 1;
}
cout << count << endl;
}
cin.get();
return 0;
}
int main()
{
int a;
while (cin >> a)
{
int count = 0;
while (a)
{
a &= a - 1;
count++;
}
cout << count << endl;
}
cin.get();
return 0;
}