// This may look like C code, but it is really -*- C++ -*-
// (The line above tells Emacs to use C++ mode to edit this file.)

// The two lines below prevent multiple-inclusion problems

#ifndef QUEUE_H
#define QUEUE_H

template <class T>
class Queue {

public:
  
  // Constructs a queue; requires the number of elements to allow.
  Queue(int num_items);

  // Destructor
  ~Queue();

  // Copy constructor
  Queue(Queue<T>& q);

  // Overloaded assignment
  const Queue<T>& operator=(const Queue<T>& q);

  // PRE: !isFull()
  // Places an item at the tail of the queue.
  void enqueue(T item);

  // PRE: !isEmpty()
  // Removes an item from the head of the queue and places it into
  // the output parameter item.
  void dequeue(T& item);

  // Returns true if the queue is empty, or false otherwise.
  int isEmpty(void);

  // Returns true if no more items will fit in the queue, or false
  // otherwise.
  int isFull(void);

private:

  // By convention, private and protected class members start with
  // the '_' character.

  int _head, _tail;		// The head and tail indices
  T *_elts;			// The array of elements.
  int _eltsSize;       		// The size of the _elts array
};

#endif