static void Main(string[] args) { Context context = new Context(new OperationAdd()); Console.WriteLine("10 + 5 = " + context.ExectureStrategy(10, 5)); context = new Context(new OperationSubstract()); Console.WriteLine("10 - 5 = " + context.ExectureStrategy(10, 5)); context = new Context(new OperationMultiply()); Console.WriteLine("10 * 5 = " + context.ExectureStrategy(10, 5)); Console.Read(); }