using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hvad er radiusen?");

        double radius = Convert.ToDouble(Console.ReadLine());

        double pi = 3.1415;

        double areal = pi * radius * radius;

        Console.WriteLine("Areal:",areal);

        Console.WriteLine(areal);

    }

}