08. Pet Shop

import java.util.Scanner;

public class PetShop {
    public static void main(String[] args) {
        double dogFoodPrice = 2.50;
        int catFoodPrice = 4;

        Scanner scanner = new Scanner(System.in);
        int dogFoodCount = Integer.parseInt(scanner.nextLine());
        int catFoodCount = Integer.parseInt(scanner.nextLine());

        double result = dogFoodPrice * dogFoodCount + catFoodPrice * catFoodCount;

        System.out.println(result + " lv.");
    }
}