static void Main(string[] args)
{
// Inheritance
Shape shape = new Shape();
Console.WriteLine(shape.Area());// returns 0 as it invokes the Area method inside the shape class
Rectangle rectangle = new Rectangle(15, 5);
Console.WriteLine(rectangle.Area());// returns 0 Even though rectangle does not have a method called area, it works because it inherited the method from the base class Shape. This is inheritence
// Method override at work - polymorphism
Shape x = new Shape();
Console.WriteLine(x.Area());
Square square = new Square(10);
Console.WriteLine(square.Area());// returns 100 Square's area method is invoked, override at work
// Another example of polymorphism
Shape z = new Rectangle(5, 2);
Console.WriteLine(z.Area()); // returns 10
// this works because you can supply a child instance in place of a parent. This is polymorphism
// // because area is a virtual method, at run time, CLR will realise that x is an instance of Rectangle, it will invoke the method from Rectangle class
}
public void PrintArea(Shape sh)
{
var a = sh.Area();
Console.WriteLine("Area: {0}", a);
}
