4. Consider an example of BASE CLASS with name SHAPE with two protected fields/data-members that are height and width, initialize the height and width in BASE CLASS using the TRADITIONAL APPROACH BASED ON ENCAPSULATION (using Setter only) Create a DERIVED CLASS with name RECTANGLE and implement getArea function (height*width) in the DERIVED CLASS.

    Consider an example of BASE CLASS with name SHAPE with two protected fields/data-members that are height and width, initialize the height and width in BASE CLASS using the TRADITIONAL APPROACH BASED ON ENCAPSULATION (using Setter only) Create a DERIVED CLASS with name RECTANGLE and implement getArea function (height*width) in the  DERIVED CLASS.

using System;

class Shape

    {

        public void setWidth(int w)

        {

            width = w;

        }

        public void setHeight(int h)

        {

            height = h;

        }

        protected int width;

        protected int height;

    }

    // Derived class

    class Rectangle : Shape

    {

        public int getArea()

        {

            return (width * height);

        }

    }

    class Program

    {

        static void Main(string[] args)

        {

            Rectangle Rect = new Rectangle();

            Rect.setWidth(5);

            Rect.setHeight(7);

            // Print the area of the object.

            Console.WriteLine("Total area: {0}", Rect.getArea());

            Console.ReadKey();

        }

    }

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