using System;

public class Program

{

    public static void Main()

    {

        int k  = 1;

        while(k == 1);

        {

            int n,i,suma;

            double masa, c;

            Console.WriteLine("Masa cegły 2.5kg");

            Console.Write("Podaj ilosc warstw:");

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

            suma = 0;

            c = 2.5;

            i = n;

            while(i>=1);

            {

                suma = suma + 1;

                i = i - 1;

            }

            masa = suma * c;

            Console.WriteLine("Ilosc cegiel:" + suma);

            Console.WriteLine("waga muru : {0:f2}", masa);

            Console.WriteLine("0/1");

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

        }

    }

}