count_bits

n = int(input("Enter a number"))
 
print(bin(n).count('1'))

#include <iostream>
 
using namespace std;
 
int main() {
  int n;
  cout << "Enter a number";
  cin >> n;
 
  int bits = 0;
  while (n > 0) {
    if ((n & 1) == 1) {
      bits++;
    }
    n >>= 1;
  }
 
  cout << bits;
}