//Custom User Interface
        //Allows user to select up to 5 toppings for its custom pizza
        public static string customUI()
        {
            Console.WriteLine();
            Console.WriteLine("Select your toppings, 5 toppings max ($1.00 each)");
            Console.WriteLine();
            Console.WriteLine("1. pepperoni            5. mushroom              c. complete choosing toppings");
            Console.WriteLine("2. chicken              6. jalapenos");
            Console.WriteLine("3. sausage              7. spinach");
            Console.WriteLine("4. bacon                8. pineapple");
            Console.WriteLine();
            int[] toppings = new int[] { 0, 0, 0, 0, 0 };
            int   i        = 0;

            do // runs through loop to populate toppings array
            {
                Console.Write("Add a topping: ");
                string topp = Console.ReadLine();
                int    topping;
                if (int.TryParse(topp, out topping))
                {
                    topping = Convert.ToInt32(topp); // each toppping has its own interger value, stored in array
                    if (topping > 0 && topping < 9)
                    {
                        //Console.WriteLine($"Added Topping  {i}");
                        toppings[i] = topping;
                        i++;
                        Console.WriteLine($"Topping Added");
                    }
                    else
                    {
                        Console.WriteLine("Invalid Input");
                    }
                }
                else if (topp == "c") // complete chosing of toppings
                {
                    i = 5;
                }
                else
                {
                    Console.WriteLine("Invalid Input");
                }
            } while (i < 5);

            Console.WriteLine();
            TypeChange type = new TypeChange();

            return(type.returnToppings(toppings)); // converts array to string of toppings then returned to options UI
        }