static void Main(string[] args) { InstrumentFactory factory = new ConcreteInstrumentFactory(); IInstrument guitar = factory.GetInstrument("Guitar"); guitar.Play(96); guitar.Sell(120); IInstrument piano = factory.GetInstrument("Piano"); piano.Play(80); piano.Sell(1000); IInstrument bass = factory.GetInstrument("Bass"); bass.Play(75); bass.Sell(150); }