Main {
{{
  static ClassGraph cg;
  public static void main(String args[]) throws Exception {
    Formula csp1 = Formula.parse(System.in);
    cg = new ClassGraph(true, false);
    csp1.print();
    System.out.println();
    Integer cI = (Integer) cg.traverse(csp1,"from Formula to Variable", 
    new Visitor() {
       int c;
       public void start() {c=0;}
       public void before (Variable host) { c++;}
       public Object getReturnValue() {return new Integer(c);}
    });
    System.out.println("number of Variables = " + cI + " done ");
    TraversalGraph tg = new TraversalGraph("from Formula to Variable", cg);
    System.out.println(tg);
  }
}}
}


Formula {
  void print() to * (PrintVisitor);
}