using System;

public class Program

{

    public static void Main()

    {

        int count=0, grade=0, avarege=0;

        Console.WriteLine("Enter your grade"); 

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

        while (grade<100)

        {

            if (grade>=70) 

            {

                count++; 

            avarege=avarege+grade; 

            }

        Console.WriteLine("Enter your grade"); 

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

        }

        Console.WriteLine ("The avarege is-\n" + (avarege)/(count));

    }

    }

​