using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Change_Tiles
{
    class Program
    {
        static void Main(string[] args)
        {
            decimal moneyGathered = decimal.Parse(Console.ReadLine());
            decimal widthFloor = decimal.Parse(Console.ReadLine());
            decimal lenghtFloor = decimal.Parse(Console.ReadLine());
            decimal sidePlate = decimal.Parse(Console.ReadLine());
            decimal heightPlate = decimal.Parse(Console.ReadLine());
            decimal pricePlate = decimal.Parse(Console.ReadLine());
            decimal priceMaistor = decimal.Parse(Console.ReadLine());
            decimal moneyNeeded = 0M;


                decimal s = widthFloor * lenghtFloor;
                decimal s1 = (sidePlate * heightPlate) / 2;
                decimal plateNeeded = s / s1;
                plateNeeded = Math.Ceiling(plateNeeded) + 5;
                moneyNeeded = (plateNeeded * pricePlate) + priceMaistor;
                if (moneyNeeded <= moneyGathered)
                {
                    Console.WriteLine("{0:F2} lv left.", moneyGathered - moneyNeeded);
                }
                else
                {
                    Console.WriteLine("You'll need {0:f2} lv more.", moneyNeeded - moneyGathered);
                }



        }
    }
}