public static void Main()
        {
            Point firstPoint = new Point(new int[2] { 5, 6 });
            Point secondPoint = new Point(new int[2] { 8, 10 });
            Console.WriteLine(firstPoint);
            Console.WriteLine(secondPoint);

            Rectangle r = new Rectangle(firstPoint, secondPoint);
            Console.WriteLine("Area of rectangle: {0}", r.Area());
            Console.WriteLine("Perimeter of rectangle: {0}", r.Perimeter());

            Parallelepiped p = new Parallelepiped(r, 2);

            Console.WriteLine(p);
            Console.WriteLine("Height of parallelepiped {0}", p.Height);
            Console.WriteLine("Volume of parallelepiped {0}", p.Volume());
        }
 public Parallelepiped(Rectangle baseSide, double height)
 {
     BaseSide = baseSide;
     Height = height;
 }
 public static double Diagonal(Rectangle r)
 {
     double diagonal = Math.Sqrt(r.Width * r.Width + r.Length * r.Length);
     return diagonal;
 }
 public Rectangle(Rectangle r)
     : this(r.upperLeft, r.lowerRight)
 {
 }
 public static double Area(Rectangle r)
 {
     double area = r.Width * r.Length;
     return area;
 }