using System;

public class Program

{ static decimal pi = 3.14159M;

    public static void Main()

    {

        start:

        Console.WriteLine("Enter 1 if you would like to calculate the volume and surface area of a cone");

        Console.WriteLine("Enter 2 if you would like to calculate the volume and surface area of a cylinder");

        Console.WriteLine("Enter 3 if you would like to calculate the volume and surface area of a sphere");

        decimal choice = decimal.Parse(Console.ReadLine());

        if (choice == 1)

        {

            Console.Clear();

            Console.WriteLine("Enter a radius");

            decimal r = decimal.Parse(Console.ReadLine());

            Console.WriteLine("Enter a height");

            decimal h = decimal.Parse(Console.ReadLine());

            Console.Clear();

            Console.WriteLine("The volume of the cone is = " + cone(r, h));

            Console.WriteLine("The surface area of the cone is = " + sacone(r,h));

            Console.WriteLine("Would you like to restart? y/n?");

            string choicee = Console.ReadLine();

            if (choicee == "y")

            {

                Console.Clear();

                goto start;

            }

        }

        if (choice == 2)

        {

            Console.Clear();

            Console.WriteLine("Enter a radius");

            decimal r = decimal.Parse(Console.ReadLine());

            Console.WriteLine("Enter a height");

            decimal h = decimal.Parse(Console.ReadLine());

            Console.Clear();

            Console.WriteLine("The volume of the cylinder is = " + cylinder(r, h));

            Console.WriteLine("The surface area of the cylinder is = " + sacylinder(r, h));

            Console.WriteLine("Would you like to restart? y/n?");

            string choicee = Console.ReadLine();

            if (choicee == "y")

            {

                Console.Clear();

                goto start;

            }

        }

            if (choice == 3)

        {

            Console.Clear();

            Console.WriteLine("Enter a radius");

            decimal r = decimal.Parse(Console.ReadLine());

            Console.Clear();

            Console.WriteLine("The volume of the sphere is = " + sphere(r));

            Console.WriteLine("The surface area of the sphere is = " + sasphere(r));

            Console.WriteLine("Would you like to restart? y/n?");

            string choiceee = Console.ReadLine();

            if (choiceee == "y")

            {

                Console.Clear();

                goto start;

            }

        }

    }

    static private decimal cone(decimal r, decimal h)

 {

    return pi * (r*r) * (h/3);

 }

    static private decimal cylinder(decimal r, decimal h)

    {

        return pi * (r*r) * h;  

    }

    static private decimal sphere(decimal r)

    {

        return 4M/3M * (pi) * (r*r*r);  

    }

    static private decimal sacone(decimal r, decimal h)

    {

        return pi*r*h + pi * (r*r); 

    }

    static private decimal sacylinder(decimal r, decimal h)

    {

        return 2 * pi * (r*r) + 2 * pi * r * h; 

    }

    static private decimal sasphere(decimal r)

    {

        return 4 * pi * (r*r);  

    }

}