using System;
public class Program
{
public static void Main()
Console.WriteLine("Enter your Marks ");
int marks = Convert.ToInt32 (Console.ReadLine());
string grade = "";
if (marks >=80)
grade = "A" ;
}
else if (marks >=60)
grade = "B" ;
else if (marks >=50)
grade = "C" ;
else if (marks >=45)
grade = "D" ;
else if (marks >=25)
grade = "E" ;
else
grade = "F";
Console.WriteLine("Your grade is " + grade );