static void Main(string[] args)
{
//Singleton Design Pattern
Console.WriteLine("Singleton Design Pattern:\n");
Singleton firstMessage = Singleton.GetInstance();
Singleton secondMessage = Singleton.GetInstance();
firstMessage.PrintMessage("First Message");
secondMessage.PrintMessage("Second Message");
//Command Design Pattern
Console.WriteLine("\nCommand Design Pattern:\n");
Product product = new Product("OnePlus 7T", 599);
ICommand increasePrice = new IncreasePriceCommand(product, 54);
ICommand decreasePrice = new DecreasePriceCommand(product, 80);
Options options = new Options(increasePrice, decreasePrice);
options.IncreasePrice();
options.DecreasePrice();
//Observer Pattern
Console.WriteLine("\nObserver Design Pattern:\n");
Subject onePlus = new Subject("OnePlus 7T", 599, "Not Available");
Subject iphone = new Subject("IPhone 11", 850, "Available");
Observer subscriber1 = new Observer("Modestas", onePlus);
Observer subscriber2 = new Observer("John", iphone);
Console.WriteLine($"OnePlus status: {onePlus.getAvailability()}");
Console.WriteLine($"Iphone status: {iphone.getAvailability()}");
onePlus.setAvailability("Available");
iphone.setAvailability("Not Available");
}
static void Main(string[] args)
{
Singleton.PrintMessage("Message From Employee");
Singleton.PrintMessage("Message From Employer");
Singleton.PrintMessage("Message From Staff");
}