using System;
using System.Linq;

namespace _07._Vending_Machine
{
    class Program
    {
        static void Main(string[] args)
        {
            string input = Console.ReadLine();
            double coins = 0;
            double currentCoin = 0;
            double price = 0;
            double amount = 0;

            while (input != "Start")
            {
                coins = double.Parse(input);
                if (coins % 0.1 == 0 || coins % 0.2 == 0 || coins % 0.5 == 0 || coins % 1 == 0 || coins % 2 == 0)
                {
                    amount += coins;
                }
                else
                {
                    Console.WriteLine($"Cannot accept {coins}");
                }
                currentCoin = coins;
                input = Console.ReadLine();

                if (input == "Start")
                {
                    string product = Console.ReadLine();
                    double currentPrice = 0;
                    while (product != "End")
                    {
                        switch (product)
                        {
                            case "Nuts":
                                price = 2.0;
                                amount -= price;
                                currentPrice = price;
                                break;
                            case "Water":
                                price = 0.7;
                                amount -= price;
                                currentPrice = price;
                                break;
                            case "Crisps":
                                price = 1.5;
                                amount -= price;
                                currentPrice = price;
                                break;
                            case "Soda":
                                price = 0.8;
                                amount -= price;
                                currentPrice = price;
                                break;
                            case "Coke":
                                price = 1.0;
                                amount -= price;
                                currentPrice = price;
                                break;
                            default:
                                Console.WriteLine("Invalid product");
                                product = Console.ReadLine();
                                break;
                        }
                        if (amount >= 0 && (amount % currentPrice == 0))
                        {
                            Console.WriteLine($"Purchased {product.ToLower()}");
                            product = Console.ReadLine();
                        }
                        if (amount < 0)
                        {
                            Console.WriteLine("Sorry, not enough money");
                            amount += currentPrice;
                            if (amount >= 0.7)
                            {
                                product = Console.ReadLine();
                            }
                        }
                    }
                  Console.WriteLine($"Change: {amount:F2}");
                }
            }
        }
    }
}