using System;

​

namespace Inherit {

    public class Shape {

        public void setWidth(int w) {

            width = w;

        }

        public void setHeight(int h) {

            height = h;

        }

        protected int width;

        protected int height;

    }

    public class Rectangle: Shape {

        protect int area;

        public int getArea() {

            area = width * height;

        }

        public void Display() {

            Console.WriteLine(area);

        }

    }

    public class RectTester {

        static void Main(string[] args) {

            Rectangle r = new Rectangle();

            r.setWidth(5);

            r.setHeight(7);

            r.getArea();

            r.Display();

        }

    }

}

​