#include <iostream> 
#include "DynIntQueue.h"
#include <cstdlib>
using namespace std;

//************************
// Constructor.          *
//************************
DynIntQueue::DynIntQueue()
{
   front = nullptr;
   rear = nullptr;
}

//************************
// Destructor.           *
//************************
DynIntQueue::~DynIntQueue()
{
   QueueNode * garbage = front;
   while (garbage != nullptr)
   {
      front = front->next;
      garbage->next = nullptr;
      delete garbage;
      garbage = front;
   }
}

//********************************************
// Function enqueue inserts the value in num *
// at the rear of the queue.                 *
//********************************************
void DynIntQueue::enqueue(int num)
{
   if (isEmpty())
   {
      front = new QueueNode(num);
      rear = front;
   }
   else
   {
      rear->next = new QueueNode(num);
      rear = rear->next;
   }
}

//**********************************************
// Function dequeue removes the value at the   *
// front of the queue, and copies it into num. *
//**********************************************
void DynIntQueue::dequeue(int &num)
{
   QueueNode *temp = nullptr;
   if (isEmpty())
   {
      cout << "The queue is empty.\n";
      exit(1);
   }
   else
   {
      num = front->value;
      temp = front;
      front = front->next;
      delete temp;
   }
}

//*********************************************
// Function isEmpty returns true if the queue *
// is empty, and false otherwise.             *
//*********************************************
bool DynIntQueue::isEmpty() const
{
   if (front == nullptr)
      return true;
   else
      return false;
}

//********************************************
// Function clear dequeues all the elements  *
// in the queue.                             *
//********************************************
void DynIntQueue::clear()
{
   int value;   // Dummy variable for dequeue

   while (!isEmpty())
      dequeue(value);
}