using System;

​

public class Point

{

    double x;

    double y;

    public Point (double X, double Y)

    {

        x=X;

        y=Y;

    }

    public double X

    {

        set{x=value;}

        get{return x;}

    }

    public double Y

    {

        set{y=value;}

        get{return y;}

    }

}

​

public class Circle

{

    double a,b,c;                           //rappresentano i parametri dell'equazione della circonferenza

    public Circle(Point p, double r)        //costruttore con un punto e un raggio

    {

        center=p;

        radius=r;

    }

    public Circle(double a, double b, double c):this(new Point(-a/2,-b/2),Math.Sqrt((a*a/4)+(b*b/4)-c))

    {

    }

    public Point center                     //rappresenta il centro con i parametri a, b, c

    {

        set{a=-2*value.X; b=-2*value.Y;}

        get{return new Point(-a/2,-b/2);} 

    }

    public double radius                    //rappresenta il raggio con i parametri a, b, c

    {

        set{c=center.X*center.X+center.Y*center.Y- value*value;}

        get{return Math.Sqrt((a*a/4)+(b*b/4)-c);}

    }

​

}

public class Program

{

    public static void Main()

    {

        Point p=new Point(1,1);

        Circle c=new Circle(8,9,10);

        Console.WriteLine(c.center.X);

        Console.WriteLine(c.center.Y);

        Console.WriteLine(c.radius);

    }

}