// A simple class hierarchy. 
 
// A class for two-dimensional objects. 
class TwoDShape { 
  double width; 
  double height; 
 
  void showDim() { 
    System.out.println("Width and height are " + 
                       width + " and " + height); 
  } 
} 
 
// A subclass of TwoDShape for triangles. 
class Triangle extends TwoDShape { 
  String style; 
   
  double area() { 
    return width * height / 2; 
  } 
 
  void showStyle() { 
    System.out.println("Triangle is " + style); 
  } 
} 
 
class Shapes { 
  public static void main(String args[]) { 
    Triangle t1 = new Triangle(); 
    Triangle t2 = new Triangle(); 
 
    t1.width = 4.0; 
    t1.height = 4.0; 
    t1.style = "filled"; 
 
    t2.width = 8.0; 
    t2.height = 12.0; 
    t2.style = "outlined"; 
 
    System.out.println("Info for t1: "); 
    t1.showStyle(); 
    t1.showDim(); 
    System.out.println("Area is " + t1.area()); 
 
    System.out.println(); 
 
    System.out.println("Info for t2: "); 
    t2.showStyle(); 
    t2.showDim(); 
    System.out.println("Area is " + t2.area()); 
  } 
}