using System;

//Martin Cingilev 18                    

public class Program

{

    public static void Main()

    {

        var town = Console.ReadLine();

        var product = Console.ReadLine();

        var num = int.Parse(Console.ReadLine());

        if (town == "Sofia")

        {

            if(product == "coffee") Console.WriteLine(num*0.5);

            else if (product == "water") Console.WriteLine(num*0.8);

            else if (product == "beer") Console.WriteLine(num*1.2);

            else if (product == "sweets") Console.WriteLine(num*1.45);

            else if (product == "peanuts") Console.WriteLine(num*1.6);

            else Console.WriteLine("Wrong product");

        }

        if (town == "Plovdiv")

        {

            if(product == "coffee") Console.WriteLine(num*0.4);

            else if (product == "water") Console.WriteLine(num*0.7);

            else if (product == "beer") Console.WriteLine(num*1.15);

            else if (product == "sweets") Console.WriteLine(num*1.30);

            else if (product == "peanuts") Console.WriteLine(num*1.50);

            else Console.WriteLine("Wrong product");

        }

        if (town == "Varna")

        {

            if(product == "coffee") Console.WriteLine(num*0.45);

            else if (product == "water") Console.WriteLine(num*0.70);

            else if (product == "beer") Console.WriteLine(num*1.10);

            else if (product == "sweets") Console.WriteLine(num*1.35);

            else if (product == "peanuts") Console.WriteLine(num*1.55);

            else Console.WriteLine("Wrong product");

        }

    }

}