using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        Circle myCircle = new Circle(20);

        Rectangle myRectangle = new Rectangle(20,30);

        Square mySquare = new Square(30);

        ShapeAreaOutputter myOutputter = new ShapeAreaOutputter();

        myOutputter.areaOutPut(myCircle);

        myOutputter.areaOutPut(myRectangle);

        myOutputter.areaOutPut(mySquare);

    }

}

​

​

//take out area outPut to Class outputter

public interface IOutputter{

     void areaOutPut(IShape shape);

}

​

public class ShapeAreaOutputter : IOutputter

{

    public void areaOutPut(IShape shape){

        Console.WriteLine("The Area of this "+shape.GetType().Name+" is "+shape.getArea());

    }

}

​

//Add Square Class - Open close

//factor out interface - Dependency Inversion Principle

​

​

public interface IShape{

​

    double getArea();

}

public class Circle : IShape{

    static double pi = 3.14159;

    private double radius {get;set;}

    public Circle(){}

    public Circle(double radius){

        this.radius = radius;

    }

    public double getArea(){

        return pi*Math.Pow(this.radius,2);

    }

}

​

public class Rectangle : IShape{

​

    protected double length {get;set;}

    protected double width {get;set;}

    public Rectangle(){}

    public Rectangle(double length,double width){

        this.length = length;

        this.width = width;

    }

    public virtual void setLength(double l){

        this.length = l;

    }

    public virtual void setWidth(double w){

        this.width = w;

    }

    public double getArea(){

        return this.length *this.width;

    }

}

​

public class Square : Rectangle{

    public Square(){}

    public Square(double side){

        this.length = side;

        this.width = side;

    }

    public override void setLength(double l){

        this.length = l;

        this.width = l;

    }

    public override void setWidth(double w){

        this.width = w;

        this.length = w;

    }

}

​

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