import java.math.BigInteger;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        BigInteger mersenne = new BigInteger("2").pow(Integer.parseInt(sc.next())).subtract(BigInteger.ONE);

        int cnt = 0;
        for (String s : mersenne.toString(2).split("")) {
            if (s.equals("1")) cnt++;
        }
        System.out.println(cnt);
    }
}