static void Main(string[] args)
{
     Leaf leaf1 = new Leaf();
     Leaf leaf2 = new Leaf();
     Leaf leaf3 = new Leaf();

     Composite composite = new Composite();
     composite.AddChild(leaf1);
     composite.AddChild(leaf2);
     composite.AddChild(leaf3);

     List <IComponent> listchildren= composite.GetChild();

     Console.WriteLine(listchildren.Count);

     leaf1.operation();
     leaf2.operation();

     composite.operation();

     Console.ReadKey();
}