using System;

public class Program

{

    public static void Main()

    {

Start;

        Console.WriteLine("What would you like to calculate the factorial of?");

        ulong ans= ulong.parse(Console.ReadLine());

            ulong fact = 1;

            for(ulong i = 1;i <=ans;i++)

                {fact *= i;}

            Console.WriteLine ans+"! = " +fact;

             Console.WriteLine("Do you want to restart? Please Enter Yes or No.");

                string answer = Console.ReadLine();

                if (answer =Yes || answer = "yes”)

                {

                    Console.Clear;

                    goTo start; }

}