using System;

​

public class Program

{

    public static String restart = "123872131";

    public static String MSG_LINE;

    public static decimal pi = 3.14159M;

    static private decimal SACone(decimal r, decimal h)

    {

        double r2 = (double)r * (double)r;

        double h2 = (double)h * (double)h;

        double slant = Math.Sqrt(r2 + h2);

        return pi * r * r + pi * r * (decimal)slant;

    }

​

    static private decimal SASphere(decimal r)

    {

        decimal r2 = r * r;

        return 4M * pi * r2;

    }

​

    static private decimal SACyl(decimal r, decimal h)

    {

        decimal r2 = r * r;

        decimal h2 = h * h;

        return 2M * pi * r2 + 2M * pi * r * h;

    }

​

    static private decimal VofCone(decimal r, decimal h)

    {

        return (1M / 3M) * pi * r * r * h;

    }

​

    static private decimal VofSphere(decimal r)

    {

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

    }

​

    static private decimal VofCylinder(decimal r, decimal h)

    {

        return pi * r * r * h;

    }

​

    public static void Main()

    {

        while (restart != "q" || restart != "Q")

        {

            Console.Clear();

            Console.WriteLine(MSG_LINE);

            Console.WriteLine("Press a to calcuate the volume of a cone");

            Console.WriteLine("Press b to calcuate the volume of a sphere");

            Console.WriteLine("Press c to calcuate the volume of a cylinder");

            String ans = Console.ReadLine();

            if (ans == "a")

            {

                Console.WriteLine("You've selected to calcuate the volume of a cone.");

                Console.WriteLine("Please enter the radius of the cone");

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

                Console.WriteLine("Please enter the height of the cone");

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

                Console.WriteLine("The volume of your cone is, " + VofCone(rcone, hcone).ToString("##.##"));

                Console.WriteLine("The surface area of your cone is, " + SACone(rcone, hcone).ToString("##.##"));

                Console.WriteLine(MSG_LINE);

                Console.WriteLine("Press q to quit, or any other key to continue the program");

                restart = Console.ReadLine();

            }

            else if (ans == "b")

            {

                Console.WriteLine("You've selected to calcuate the volume of a sphere.");

                Console.WriteLine("Please enter the radius of the sphere");

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

                Console.WriteLine("The volume of your sphere is, " + VofSphere(rcone).ToString("##.##"));

                Console.WriteLine("The surface area of your cone is, " + SASphere(rcone).ToString("##.##"));

                Console.WriteLine(MSG_LINE);

                Console.WriteLine("Press q to quit, or any other key to continue the program");

                restart = Console.ReadLine();

            }

            else if (ans == "c")

            {

                Console.WriteLine("You've selected to calcuate the volume of a cylinder.");

                Console.WriteLine("Please enter the radius of the cylinder");

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

                Console.WriteLine("Please enter the height of the cylinder");

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

                Console.WriteLine("The volume of your cylinder is, " + VofCylinder(rcylinder, hcylinder).ToString("##.##"));

                Console.WriteLine("The surface area of your cylinder is, " + SACyl(rcylinder, hcylinder).ToString("##.##"));

                Console.WriteLine(MSG_LINE);

                Console.WriteLine("Press q to quit, or any other key to continue the program");

                restart = Console.ReadLine();

            }

            else

            {

                Console.WriteLine("Invalid user input. Please select a function");

            }

        }

    }

}