using System;

public class Program

{

    public static void Main()

    {

        Shape[] myArray = {new Rectangle(6, 7),new Circle(2)};

        AreaCalculator recCalculator = new AreaCalculator();

        Console.WriteLine("area is: "+recCalculator.TotalArea(myArray));

    }

}

​

​

public abstract class Shape

{

    public abstract double Area();

}

​

public class Rectangle: Shape

{  

    public double Height {get;set;}  

    public double Width {get;set; }  

    public Rectangle(double _Height, double _Width)

    {

        Height = _Height;

        Width = _Width;

    }

    public override double Area()

    {

        return Width*Height;

    }

}

​

public class Circle : Shape

{

    public double Radius {get;set;}

    public Circle(double _Radius)

    {

        Radius = _Radius;

    }

    public override double Area()

    {

        return Radius * Radius * 3.14;

    }

}

​

public class AreaCalculator

{

    public double TotalArea(Shape[] recArray)

    {

        double area = 0;

        foreach (var rec in recArray)

        {

            area += rec.Area();

        }

        return area;

    }

}

​