#ifndef TREE_H
#define TREE_H

#include <iosfwd>

class Tree
{
public:

  Tree()
    : root_(0) {}
  ~Tree()
  {
    clear();
  }
  void insert(int);
  void remove_root();
  void print(std::ostream & = std::cout, int = 1) const;
  bool member(int) const;
  void clear();
  bool empty() const;
  
private:
  // Private copy constructor and assignment operator prevents
  // unintentional shallow copies.
  Tree(const Tree&);
  Tree &operator=(const Tree &);

  struct Tree_Node * root_;

  // Recursive help-functions
  void insert(int, Tree_Node *&);
  void print(std::ostream &, const Tree_Node *, int) const;
  bool member(int, const Tree_Node *) const;
};

#endif