using System;

public class Program

{

    public static void Main()

    {

        double grade1, grade2, sum1, sum2, min=100;

        for(int i=1; i<=3; i++)

        {

        Console.WriteLine("enter your first grade");

            grade1=int.Parse(Console.ReadLine());

            Console.WriteLine("enter your seconde grade");

            grade2=int.Parse(Console.ReadLine());

            sum1=grade1+grade2;

            sum2=sum1/2;

            Console.WriteLine("your average is "+sum2);

            if(min>sum2)

            {

                min=sum2;

            }

        }

        Console.WriteLine("the lowest average is "+min);

    }

}