import java.util.Scanner;


public class prog {
    public static void main (String[] args) throws java.lang.Exception
    {
        Scanner scanner = new Scanner(System.in);
        int n = Integer.parseInt(scanner.nextLine());
        if(n % 2 == 0){
            if(n/2 % 2 == 0){
                System.out.println(15);
            } else {
                System.out.println(16);
            }
        } else {
            if((n-1)/2 % 2 == 0){
                System.out.println(16);
            } else {
                System.out.println(15);
            }
        }
        scanner.close();
    }
}