abstract class Vessel {
  double contents;

  abstract double volume();

  abstract double circumf();

  public void fill(double amount) {
    contents = contents + amount;
    contents = Math.min(contents, volume());
  }
}

class Tank extends Vessel {
  double length, width, height;

  Tank(double length, double width, double height) { 
    this.length = length; this.width = width; this.height = height; 
  }

  double volume() { 
    return length * width * height; 
  }

  double circumf() {
    return 2 * (width + length);
  }
}

class Barrel extends Vessel {
  double radius, height;

  Barrel(double radius, double height) { 
    this.radius = radius; this.height = height; 
  }

  double volume() { 
    return height * Math.PI * radius * radius; 
  }

  double circumf() {
    return 2 * Math.PI * radius;
  }
}

public class Vessel9 {
  public static void main(String[] args) {
    Vessel v1 = new Tank(15, 9, 12);
    Vessel v2 = new Barrel(2.5, 8);

    v1.fill(100);
    System.out.println("Indhold af v1 = " + v1.contents);  
    v1.fill(2000);
    System.out.println("Indhold af v2 = " + v1.contents);  

    v2.fill(500);
    System.out.println("Indhold af v2 = " + v2.contents);  
  }
}