using System;

​

public class Program

{

    public static void Main()

    {

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

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

        var typeTrace = Console.ReadLine().ToLower();

        double[] junTax = {5.50, 8.0, 12.25, 20};

        double[] seniorTax = {7.0, 9.50, 13.75, 21.50};

        var resJ =0.0;

        var crossCase = junior + senior;

        if(typeTrace == "trail")

        {

            resJ += junTax[0] * junior;

        }

        else if(typeTrace == "downhill")

        {

            resJ += junTax[2] * junior;

        }

        else if(typeTrace == "road")

        {

            resJ += junTax[3] * junior;

        }

        else if(typeTrace == "cross-country")

        {

            resJ += junTax[1] * junior;

        }

        // --------------------------------------------     

        if(typeTrace == "trail")

        {

            resJ += seniorTax[0] * senior;

        }

        else if(typeTrace == "downhill")

        {

            resJ += seniorTax[2] * senior;

        }

        else if(typeTrace == "road")

        {

            resJ += seniorTax[3] * senior;

        }

        else if(typeTrace == "cross-country")

        {

            resJ += seniorTax[1] * senior;

        }

        var tax = resJ - (resJ*0.05);

        if(crossCase>=50 && typeTrace == "cross-country")

        {

            tax-=(tax*0.25);            

            Console.WriteLine("{0:f2}", tax);

        }

        else

        {           

            Console.WriteLine("{0:f2}", tax);

        }   

    }

}