using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }int Booknum,Bookprice,Sum;

}Console.WriteLine("ادخل عدد الكتب");

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

Console.WriteLine("ادخل سعور الكتاب");

Bookprice=doube.parse(Console.ReadLine());

Sum=Bookprice*Booknum

Console.WriteLine("the sum is{0}",sum);