using System;

public class Program

{

    public static void Main(string[] args)

    {

        double Pi = 3.14;

        Console.WriteLine("Sisesta raadius (cm): ");

        double r = 0 ;

        string radiusAsTxt = string.Empty;

        radiusAsTxt = Console.ReadLine();

        bool isNumberDouble = double.TryParse(radiusAsTxt, out r);

    }

}