using System;

public class Program

{

    public static void Main()

    {

        int Marks;

        Console.WriteLine("What is your mark");

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

        if (Marks >= 80)

        {

            Console.WriteLine("You got an A");

        }

        else if (Marks >= 70 && Marks < 80)

        {

            Console.WriteLine("You got a B");

        }

        else if (Marks >= 55 && Marks < 70)

        {

            Console.WriteLine("You got a C");

        }

        else if (Marks >= 45 && Marks < 55)

        {

            Console.WriteLine("You got a D");

        }

        else if (Marks >=30 && Marks < 45)

        {

            Console.WriteLine("You got an E");

        }

        else

        {

            Console.WriteLine("You Failed");

        }

    }

}