PetShop_SoftUni

using System;

namespace softuni1
{
    class Program
    {
        static void Main(string[] args)
        {
            double s = 2.50;
            double d = 4;
            double sKucheta = double.Parse(Console.ReadLine());
            double dKucheta = double.Parse(Console.ReadLine());

            double sumS = sKucheta * s;
            double sumD = dKucheta * d;
           double total = sumS + sumD;

            Console.WriteLine($"{total} lv.");



        }

    }
}