// package base; 
import java.util.*;
abstract class Item {
  String name;
  public abstract int weight();
}
class Container extends Item {
  Vector elements;
  int capacity;
  public Container(String name, int cap) {
    this.name = name;
    this.capacity = cap;
    this.elements = new Vector();
  }
  public void addItem(Item i) {  /*\label{line:cont-addItem}*/
    elements.add(i);
  }
  public int weight() {  /*\label{line:cont-weight}*/
    Iterator it = elements.iterator();
    int total = 0;
    while (it.hasNext()) {
      Item child = (Item)it.next();
      total += child.weight();
    }
    System.out.println(
       "Container " + name
       + " weighs " + total); 
    return total;
  }
  public void check() {  /*\label{line:cont-check}*/
    int total = weight();
    if (total>capacity){
       System.out.println(
           "Container " + name
           + " overloaded");
    }
  }
  /* Q: What is this for?  A: because we hate constructors.*/
//  public static Container make(
//                     String n,int c) {
//        return new Container(n,c);
//  }
}