static void Main(string[] args) { Console.WriteLine(" ** This is Duck Fly Learning Program from Head First Design Patterns \n Chap 1 - Strategy Pattern ** \n\n"); Duck mallard = new MallardDuck(); mallard.display(); mallard.performQuack(); mallard.performFly(); Console.WriteLine(); Duck redhead = new RedheadDuck(); redhead.display(); redhead.performQuack(); redhead.performFly(); Console.WriteLine(); Duck rubber = new RubberDuck(); rubber.display(); rubber.performQuack(); rubber.performFly(); Console.WriteLine(); Console.WriteLine("Adding Rocket Power to Rubber Duck"); Console.WriteLine(); // setting fly behavior for rubber ducky rubber.setFlyBehavior = new FlyRocketPowered(); rubber.display(); rubber.performFly(); }