public class Verkauf {
  private Liste posten;

  private void add(Ware w, int c ) {
    Liste hl = new Liste(new Warenbestand(w, c));
    if ( posten == null ) {
      posten = hl;
    } else {
      posten.append(hl);
    }
  }

  public void transfer(Warenlager source, Ware w, int c) {
    Liste b;
    for (b = source.bestand; b != null; b = b.next) {
      if ( ((Warenbestand)b.data).ware == w ) {
        if( ((Warenbestand)b.data).count >= c ) {
          ((Warenbestand)b.data).count -= c;
          add(w, c);
        } else {
          System.err.print("Nicht genügend Ware vorhanden\n");
        }
        return;
      }
    }
  }
  
  public String toString() {
    Liste p; String r = "";
    for (p = posten; p != null; p = p.next) {
      r += p.data.toString() + "\n";
    }
    r += String.format("%52.2f\n", wert());
    return r;
  }
  
  public double wert() {
    double r = 0.0; Liste b;
    for (b = posten; b != null; b = b.next) {
      r += ((Warenbestand) b.data).wert();
    }
    return r;
  }
}