#include <iostream>

using namespace std;

int main()
{
    int a;
    cin >> a;
    if (a < 0 || a >= 32) {
        cout << "Error";
    }
    else {
        int b = 0;
        while (a) {
            b += a % 2;
            a /=2;
        }
        cout << b;
    }
    return 0;
}