using System;

public class Program

{

    public static void Main()

    {

        decimal amountOfMoney = decimal.Parse(Console.ReadLine());

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

        decimal sabrePrice = decimal.Parse(Console.ReadLine());

        decimal robePrice = decimal.Parse(Console.ReadLine());

        decimal beltPrice = decimal.Parse(Console.ReadLine());

        decimal totalPrice = sabrePrice * (countOfStudents + (10/100)) + robePrice * (countOfStudents) + beltPrice * (countOfStudents);

        int freeBelt = 0;

        if(countOfStudents % 6 == 0)

        {

            freeBelt +=1;

            totalPrice =  sabrePrice * (countOfStudents + (10/100)) + robePrice * (countOfStudents) + beltPrice * (countOfStudents-freeBelt);

            Console.WriteLine(totalPrice);

        }

        Console.WriteLine(totalPrice);

    }

}