Java lab 1 (30/10/2023)

interface Shape
{
    final static double pi=3.14;
    abstract void ComputeArea(double x,double y);
}
class Rectangle implements Shape
{
    public void ComputeArea(double x,double y)
    {
        double area;
        area=x*y;
        System.out.println("area= "+area);
    }
}
class Circle implements Shape {
    public void ComputeArea(double x, double y)
    {
        double area_circle;
        area_circle=pi*x*x;
        System.out.println("Circle area= "+area_circle);
    }
}

public class InterfaceDemo
{
    public static void main(String[] args)
    {
        Shape ob;
        Rectangle rect=new Rectangle();
        ob=rect;
        ob.ComputeArea(10.0,20.0);
        Circle circ=new Circle();
        ob=circ;
        ob.ComputeArea(10.0,0.0);
    }
}