public class A
        {
            public virtual void Print1()
            {
                Console.WriteLine("A.print1");
            }
           
        }
        public class B : A
        {
            public /*override*/ void Print1()
            {
                Console.WriteLine("B.print1");
            }
        }


        public static void Main(string[] args)
        {           
            A b = new B();
        
            b.Print1();         
        }

        public class Cat
        {
            public void Speak()
            {
                Console.WriteLine("Cat.meow");
            }
           
        } 
        public class Tiger : Cat
        {                                     
            public new void Speak()
            {
                Console.WriteLine("Tiger.rrr");
            }
        }


        public static void Main(string[] args)
        {
            Cat a = new Cat();
            Cat b = new Tiger();
            a.Speak();
            b.Speak();

            //Console.WriteLine(b.GetType().Name);                     
        }