using System;

public class Program

{

    public static void Main()

    {

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

        switch (grade)

        {

            case 2:

                Console.WriteLine("Слаб");

                break;

            case 3:

                Console.WriteLine("Среден");

                break;

            case 4:

                Console.WriteLine("Добър");

                break;

            case 5:

                Console.WriteLine("Много добър");

                break;

            case 6:

                Console.WriteLine("Отличен");

                break;

            default:

                Console.WriteLine("Грешка");

                break;      

        }

    }

}