using System;

public class Program

{

    public static void Main()

    {

   int chislo = int.Parse(Console.ReadLine());

        if ((chislo>=1) && (chislo<=100) && (chislo%2 == 0))

        {

       Console.WriteLine("valid");

        }

​

       else 

        {

            Console.WriteLine("not valid");

        }

   }