using System;

public class Program

{

    public static void Main()

    {

        /*

        Console.Writeline("   *);

        Console.Writeline("  ***");

        Console.Writeline(" *****");

        Console.Writeline("*******");

        */

        int so; 

        System.Console.WriteLine("Nhap mot so:");

        so = Convert.ToInt32(System.Console.ReadLine());

        int soDu = so %3;

        Console.Write(soDu);

        if(soDu==0)//neu soDu=0

            System.Console.WriteLine("Phep chia het, khong du");

        else if(soDu==1)

            Console.WriteLine("Du 1!");

        else

            Console.Writeline("Du 2!");

    }

}