using System;

namespace _08._Fruit_Shop
{
    class Program
    {
        static void Main(string[] args)
        {
            string fruit = Console.ReadLine();
            string dayOfWeek = Console.ReadLine();
            double quantity = double.Parse(Console.ReadLine());

            bool isDays = dayOfWeek == "Monday" || dayOfWeek == "Tuesday" || dayOfWeek == "Wednesday" ||
                dayOfWeek == "Thursday" || dayOfWeek == "Friday" || dayOfWeek == "Saturday" || dayOfWeek == "Sunday";
            bool isFruit = fruit == "banana" || fruit == "apple" || fruit == "orange" || fruit == "grapefruit" ||
                fruit == "kiwi" || fruit == "pineapple" || fruit == "grapes";
            bool isWeekDays = dayOfWeek == "Monday" || dayOfWeek == "Tuesday" || dayOfWeek == "Wednesday" ||
                dayOfWeek == "Thursday" || dayOfWeek == "Friday";
            bool isHolidays = dayOfWeek == "Saturday" || dayOfWeek == "Sunday";

            if (isFruit && isDays)
            {
                if (isWeekDays)
                {
                    if (fruit == "banana")
                    {
                        Console.WriteLine($"{quantity * 2.5:F2}");
                    }
                    else if (fruit == "apple")
                    {
                        Console.WriteLine($"{quantity * 1.2:F2}");
                    }
                    else if (fruit == "orange")
                    {
                        Console.WriteLine($"{quantity * 0.85:F2}");
                    }
                    else if (fruit == "grapefruit")
                    {
                        Console.WriteLine($"{quantity * 1.45:F2}");
                    }
                    else if (fruit == "kiwi")
                    {
                        Console.WriteLine($"{quantity * 2.7:F2}");
                    }
                    else if (fruit == "pineapple")
                    {
                        Console.WriteLine($"{quantity * 5.5:F2}");
                    }
                    else if (fruit == "grapes")
                    {
                        Console.WriteLine($"{quantity * 3.85:F2}");
                    }
                }
                else if (isHolidays)
                {
                    if (fruit == "banana")
                    {
                        Console.WriteLine($"{quantity * 2.7:F2}");
                    }
                    else if (fruit == "apple")
                    {
                        Console.WriteLine($"{quantity * 1.25:F2}");
                    }
                    else if (fruit == "orange")
                    {
                        Console.WriteLine($"{quantity * 0.90:F2}");
                    }
                    else if (fruit == "grapefruit")
                    {
                        Console.WriteLine($"{quantity * 1.6:F2}");
                    }
                    else if (fruit == "kiwi")
                    {
                        Console.WriteLine($"{quantity * 3:F2}");
                    }
                    else if (fruit == "pineapple")
                    {
                        Console.WriteLine($"{quantity * 5.6:F2}");
                    }
                    else if (fruit == "grapes")
                    {
                        Console.WriteLine($"{quantity * 4.2:F2}");
                    }
                }
            }

            else
            {
                Console.WriteLine("error");
            }
//Магазин за плодове през работните дни работи на следните цени:
//плод    banana  apple orange  grapefruit kiwi    pineapple grapes
//цена    2.50    1.20    0.85    1.45    2.70    5.50    3.85
//Събота и неделя магазинът работи на по - високи цени:
//плод    banana  apple orange  grapefruit kiwi    pineapple grapes
//цена    2.70    1.25    0.90    1.60    3.00    5.60    4.20

        }
    }
}