using System;

​

public class Program

{

    public static void Main()

    {

        double ocenka = double.Parse(Console.ReadLine());

        if (ocenka < 2.50)

        {

            Console.WriteLine("слаб");

        }

        else if (ocenka < 3.50)

        {

            Console.WriteLine("среден");

        }

        else if (ocenka < 4.50)

        {

            Console.WriteLine("доб");

        }

    }

}