public override void VisitRectangle(Rectangle r)
{
Result += r.TopLeft.X + r.Width;
}
public override void VisitRectangle(Rectangle r)
{
Result += r.TopLeft.Y + r.Length;
}
public abstract void VisitRectangle(Rectangle r);
public override void VisitRectangle(Rectangle r)
{
Result += r.Area;
}