Non_Decorator.cs

class Party
    {
        public void Cost()
        {
            Console.WriteLine("Detail: Party, Price: 200");
        }
    }

    class PartyWithAlcohol
    {
        public void Cost()
        {
            Console.WriteLine("Detail: Party and Alcohol, Price: 250");
        }
    }

    class PartyWithAlcoholAndGirl
    {
        public void Cost()
        {
            Console.WriteLine("Detail: Party and Alcohol and Girl, Price: 1250");
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Party A = new Party();
            A.Cost();
            PartyWithAlcohol B = new PartyWithAlcohol();
            B.Cost();
            PartyWithAlcoholAndGirl C = new PartyWithAlcoholAndGirl();
            C.Cost();

            Console.ReadLine();
        }
    }