import java.util.*;
public class main{
    public static void main(String [] args){
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        if(a<0){
            System.out.println("Invalid input");
            Systemexit(0);
        }
        String octal = Integer.toOctalString(a);
        System.out.println(octal);
    }
}