C++ Queue Template

[taylor0934]

I am having trouble starting, I have the default constructor. Just set Head, Tail, Pred and Succ equal to 0. The copy constructor I am having problems with, don't know where to start.

enum Direction { front_to_back, back_to_front };

template <typename EType>
class PQueue
{
  private:
 
    struct Node
    {
      EType Item;
      unsigned Priority;
      unsigned Identifier;
      Node * Pred;
      Node * Succ;
    };
 
    Node * Head;    // Pointer to head of chain (front)
    Node * Tail;    // Pointer to tail of chain (back)

  public:

    // Initialize pqueue to empty
    //
    PQueue();

    // De-initialize pqueue
    //
    ~PQueue();

    // Re-initialize pqueue to empty
    //
    void reset();

    // Initialize pqueue using existing pqueue