#ifndef PRIORITYQUEUE
#define PRIORITYQUEUE

#include "Exceptions.h"

/*
 *  This defines a less-generic form of a priority queue which has
 *  only a single template parameter, for the element type.
 *
 *  They key must be of type double and the comparisons will be based upon
 *  the standard built-in less-than operator.
 */
template <typename Element>
class PriorityQueue { 
public:

  // number of items
  virtual int size() const =0;  

  // is the queue empty?
  virtual bool isEmpty() const =0;  

  // insert into queue
  virtual void insertItem(double k, const Element& e) =0;   

  // returns element with min key
  virtual Element& minElement() throw(EmptyContainerException) =0;

  // returns minimum key
  virtual double minKey() const throw(EmptyContainerException) =0;

  // remove minimum
  virtual void removeMin() throw(EmptyContainerException) =0;

  // destructor
  virtual ~PriorityQueue() {};
};

#endif