static void Main(string[] args)
{
// just like service layer in web application
//sample 1
CalculationFacade facade = new CalculationFacade();
Console.WriteLine(facade.Calculate(20));
Console.ReadKey();
}
static void Main(string[] args)
{
// Instead of using the subsystem which is rich on functions
// the client uses the facade which simplifies the usage
CalculationFacade easyToUseInterface = new CalculationFacade();
int a = 4;
int b = 2;
int result = easyToUseInterface.DoComplexCalculation(a, b);
Console.ReadLine();
}