static void Main(string[] args) { CompositeElement root = new CompositeElement("Picture"); root.Add(new PrimitiveElement("Red Line")); root.Add(new PrimitiveElement("Blue Circle")); root.Add(new PrimitiveElement("Green Box")); CompositeElement comp = new CompositeElement("Two Circles"); comp.Add(new PrimitiveElement("Black Circle")); comp.Add(new PrimitiveElement("White Circle")); root.Add(comp); // Add and remove a PrimitiveElement PrimitiveElement pe = new PrimitiveElement("Yellow Line"); root.Add(pe); root.Remove(pe); // Recursively display nodes root.DisPlay(1); Console.ReadKey(); }