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faiz 0 Newbie Poster

plz help me in debugging a program(urgent).it's the implementation of ascending and descending priority queues using array.i've made a program but it is not functioning properly.the problem is that when i initialize the array in the class the ascending priority queue stores only zeros and the descending priority queue is ok but if i don't initialize it the descending priority queue stores some garbage value instead of items inserted in it + the first element inserted in the queue is zero not the element inserted by the user.i'm in 2nd semester in software engineering and just a begginer in programming.so plz help with basic c++.faiz

priority queue using array.cpp

# include <iostream.h>
# include <conio.h>
# include <string.h>


const int MAX=50;

class prqueue
{
   private:
     int front;
     int rear;
	   int length;          //to keep the track of elements present in the queue
     int pqu[MAX];


//---------------------------------------------------------------------
  public:

    prqueue()
    {
    //for(int i=0;i<MAX;i++)
    //{
    //pqu[i]=0;
    //}
      front=0;
      rear=0;
      length=0;
    }

//------------------------------------------------------------------------
    bool isempty()
    {
      if (length)
	      return 0;
 	    return 1;
    }

//----------------------------------------------------------------------

    bool isfull()

    {
      if (length==MAX)
	      return 1;
 	    return 0;
    }

//----------------------------------------------------------------------
void aswap()                         //to arrange the elements in the queue
{
 for (int j=front;j<rear;j++)
 {
   for (int i=front;i<rear;i++)
   {
     if (pqu[i]>pqu[i+1])
     {
       int temp;
       temp=pqu[i];
       pqu[i]=pqu[i+1];
       pqu[i+1]=temp;
     }

   }
 }
}
//----------------------------------------------------------------------
   void apqinsert(int item)
    {

      if (isfull())
      {
        cout << "The queue is full,plz delete an object before inserting." << endl;
        return;
      }
      pqu[rear++]=item;
      length++;
      aswap();
    }
//-------------------------------------------------------------------------

    int apqdelete()
    {
      int item;
      if (isempty())
      {
        cout << "the queue is empty,plz insert an item before deleting another" << endl;
        getch();
        return -100000;
      }
      item=pqu[front++];
      length--;
      return item;
    }

//----------------------------------------------------------------------------
    void dswap()
    {

      for (int i=front;i<rear;i++)
      {
        for (int j=front;j<rear;j++)
        {
          if (pqu[j]<pqu[j+1])
          {
            int temp;
            temp=pqu[j];
            pqu[j]=pqu[j+1];
            pqu[j+1]=temp;
          }
        }
      }
    }

//---------------------------------------------------------------------------

  void dpqinsert(int item)
  {
    if (length==MAX)
    {
      cout << "the queue is full.plz delete an item before inserting another" << endl;
      cout << "press any key to continue...";
      getch();
      return;
    }
    pqu[rear++]=item;
    dswap();
    length++;

  }
//----------------------------------------------------------------------------

  int dpqdelete()
  {
    int item;
    if (isempty())
    {
      cout << "the queue is empty.plz insert an item before attempting to delete" << endl;
      cout << "press any key to continue...";
      getch();
      return false;
    }
    item=pqu[front++];
    length--;
    return item;
  }

//----------------------------------------------------------------------------

    void qdisplay()
    {
      cout << "the queue is: ";
      for (int i=front;i<rear;i++)
      {
        cout << pqu[i] <<"\t";
      }
      cout << endl;
    }

};//end of class

//=============================================================================

int main()
{
  prqueue pq,pq2;
  int item;
  char ch;
  char option;

  do
  {
    clrscr();
    cout << "what do u want to do?\n";
    cout << "enter choice acc. to choice\n";
    cout << "menu is: " << endl;
    cout << "1-insert and item in ascending priority queue\n";
    cout << "2-delete an item from ascending priority\n";
    cout << "3-insert an item in descending priority queue\n";
    cout << "4-delete an item from descending priority queue\n";
    cout << "press x to exit the program\n";
    cout << "your choice is: ";
    cin >> option;

    switch (option)
    {
      case '1':

        do
        {
         cout << "enter item to insert: ";
         cin >> item;
         //if (item!= 0||item!=1||item!=2||item!=3 ||item!=4||item!=5||item!=6||item!=7||item!=8||item!=9)
         //{
           //cout << "invalid input,plz input integers" << endl;
           //break;
         //}
         pq.apqinsert(item);
         pq.qdisplay();

         cout << "do u want to insert another(y/n) ";
         cin >> ch;
        }while(ch!='n');
        break;


      case '2':

        item=pq.apqdelete();
        cout << item << " has been deleted from the priority queue" << endl;
        pq.qdisplay();
        cout << "press any key to continue..." << endl;
        getch();
        break;

      case '3':


        do{
          cout << "enter an item to insert";
          cin >>item;
          pq2.dpqinsert(item);
          pq2.qdisplay();
          cout << "do you want to insert another(y/n)";
          cin >> ch;
        }while (ch=='y');

        break;
      case '4':

        item=pq2.dpqdelete();
        cout << item << "has been deleted from the priority queue" << endl;
        pq2.qdisplay();
        cout << "press any key to continue...";
        getch();
        break;
      }


  }while (option!='x');

  cout << "exiting the program...press any key";

  getch();
  return 0;
}
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