using System;

public class Program

{

    public static void Main()

    {

           int ownDogs = int.Parse(Console.ReadLine());

            int otherAnimals = int.Parse(Console.ReadLine());

            double dogfoodPrice = 2.50;

            double animalfoodPrice = 4;

            double totaldogfoodPrice = ownDogs * dogfoodPrice;

            double totalanimalfoodPrice = otherAnimals * animalfoodPrice;

            double sum = totalanimalfoodPrice + totaldogfoodPrice;

            Console.WriteLine( sum+"lv.");

​

​

​

    }

}