class PCacheHash : public PermHash {
  int cap_;
  int n_buckets;
  Queue<T> retirementQueue;
  T **buckets;

public:
  PCacheHash(const char*, int, int, int);
  virtual ~PCacheHash();

  virtual bool remove(const char*);
  virtual bool find(const char*, T&);
  virtual bool update(const T&);

private:
  bool getPosFor(const char*, int&, int&);
  void eraseItemAt(int, int);
};