import java.util.*;
public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  }
} import java.util.*; util.* java public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  }
} Main public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  } main { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int cnt = 0; cnt 0 for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      } int i = 0; int i = 0; i 0 i < 3 i 3 i++ i++ i {
        if((n >> i & 1) == 1) cnt++;
      } {
        if((n >> i & 1) == 1) cnt++;
      } if((n >> i & 1) == 1) cnt++; (n >> i & 1) == 1 (n >> i & 1) n >> i n i 1 1 cnt++ cnt System.out.println(cnt) System.out.println System.out System System.out cnt String[] args args public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  }
} public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  }
} Main
import java.util.*;
public class Main {

  public static void main(String[] args) { 
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int cnt = 0;
      for(int i = 0; i < 3; i++) {
        if((n >> i & 1) == 1) cnt++;
      }
      System.out.println(cnt);
  }
}