package com.company;
import java.util.Scanner;
public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        double firstRow=Double.parseDouble(scanner.nextLine());
        double secondRow=Double.parseDouble(scanner.nextLine());

        String thirdRow=scanner.nextLine();

        double priceJ=0;
        double totalUchastnici=firstRow+secondRow;

        switch(thirdRow){
            case "trail":
                priceJ=firstRow*5.50+secondRow*7;

                break;
            case "cross-country":

                if(totalUchastnici>=50)
                {
                    priceJ=(firstRow*8+secondRow*9.50)*0.75;

                }else
                {
                    priceJ=firstRow*8+secondRow*9.50;
                }
                break;
            case "downhill":
                priceJ=firstRow*12.25+secondRow*13.75;
                break;
            case "road":
                priceJ=firstRow*20+secondRow*21.50;;

                break;
        }
        System.out.printf("%.2f",priceJ*0.95);
    }
}