using System;

namespace _08._Fruit_Shop
{
    class Program
    {
        static void Main(string[] args)
        {
            // 	banana	apple	orange	grapefruit	kiwi	pineapple	grapes
            //   2.50    1.20    0.85     1.45      2.70        5.50      3.85

            //banana	apple	orange	grapefruit	kiwi	pineapple	grapes
            // 2.70      1.25    0.90      1.60     3.00       5.60      4.20


            string fruit = Console.ReadLine();
            string day = Console.ReadLine();
            double quantity = double.Parse(Console.ReadLine());

            double price = 0;



            if (day == "Monday" || day == "Tuesday" || day == "Wednesday" || day == "Thursday" || day == "Friday")
            {
                switch (fruit)
                {
                    case ("banana"):
                        price = 2.50;
                        break;
                    case ("apple"):
                        price = 1.20;
                        break;
                    case ("orange"):
                        price = 0.85;
                        break;
                    case ("grapefruit"):
                        price = 1.45;
                        break;
                    case ("kiwi"):
                        price = 2.70;
                        break;
                    case ("pineapple"):
                        price = 5.50;
                        break;
                    case ("grapes"):
                        price = 3.85;
                        break;
                    default:
                        Console.WriteLine("error");
                        break;

                }
                double totalPrice = price * quantity;
                Console.WriteLine($"{totalPrice:F2}");
            }
            else if (day == "Saturday" || day == "Sunday")
            {
                switch (fruit)
                {
                    case ("banana"):
                        price = 2.70;
                        break;
                    case ("apple"):
                        price = 1.25;
                        break;
                    case ("orange"):
                        price = 0.90;
                        break;
                    case ("grapefruit"):
                        price = 1.60;
                        break;
                    case ("kiwi"):
                        price = 3.00;
                        break;
                    case ("pineapple"):
                        price = 5.60;
                        break;
                    case ("grapes"):
                        price = 4.20;
                        break;
                    default:
                        Console.WriteLine("error");
                        break;

                }
                double totalPrice = price * quantity;
                Console.WriteLine($"{totalPrice:F2}");
            }
            else
            {
                Console.WriteLine("error");
            }







        }
    }
}