static void Main(string[] args)
{
Rectangle rec = new Rectangle(-1, -1);
Circle circle = new Circle(-1);
Triangle tri = new Triangle(1, 2, 3);
rec.showInfo();
circle.showInfo();
tri.showInfo();
Console.WriteLine();
Rectangle rec1 = new Rectangle(10, 20);
Circle circle1 = new Circle(5);
Triangle tri1 = new Triangle(2, 2, 3);
rec1.showInfo();
circle1.showInfo();
tri1.showInfo();
}