using System;

public class Rectangle

{

    //interface

    interface RectInterface{

      int Length(); 

      int Width(); 

    }

    class RectDimensions:RectInterface{

        public int Length(){

            return 50; 

        }

​

        public int Width(){

            return 40; 

​

        }

    }

    class Area : RectDimensions{

      public int calcArea(){

        return  Length() * Width(); 

       }

    }

    //Main method 

    public static void Main(){

        //Console.WriteLine("Joe Testing Interface here :) ");

        //create Object 

        Area AreaValue = new Area(); 

        Console.WriteLine(AreaValue.calcArea());  

    }

}