using System;

public class Program

{

    public static void Main()

    {

        int mark = 0;

        String grade = "";

        Console.WriteLine("Please enter a grade");

        mark = Convert.ToInt32(Console.ReadLine());

        if(mark > 80)

        Console.WriteLine(grade = "Grade is A");

        else

        Console.WriteLine("You Failed");

    }

​

    }

​