public static void ExampleCode5()
        {
            IShape shape1 = new Rectangle(10.0F, 20.3F);
            IShape shape2 = new Rectangle(5.0F, 17.3F);

            Console.WriteLine("Area of the Rectangle-1 is {0} ", shape1.CalculateArea());
            Console.WriteLine("Area of the Rectangle-2 is {0} ", shape2.CalculateArea());

            Rectangle shape3 = (Rectangle)shape1 + (Rectangle)shape2;

            Console.WriteLine("Area of the Rectangle-3 is {0} ", shape3.CalculateArea());

            string result = shape3.Process <string>("list");

            int out1 = shape1.Display <int>(1);
            int out2 = shape2.Display <int>(2);
        }