using System;

public class Program

{

    public static void Main()

    {

        int number(h); int price(h); money;

        number(h)=int.parse(Console.Readline));

        price(h)=int.parse(ConsoleReadline));

        money=(number(h)*price(h));

        if (money<4500);

        {

            Console.writeline(money);

        }

        if (money>4500 && money<7000);

                Console.writeline(money*0.2);

        }

        if (money>7000);

        {

            Console.writeline(money-700);

    }

}