//12D Program-19 Array Queue Insertion and Deletion

//12D Program-19 Array Queue Insertion and Deletion

#include<iostream.h>

// #include<stdlib.h>

#include<process.h>

#include<conio.h>

int Remove(int []);

int Insert(int [], int);

void Display(int [], int, int);

const int size = 50;

int Queue[size],front=-1,rear=-1;

int main()

{

   int Item,res; char ch='Y';

   clrscr();

   while( ch=='y'||ch=='Y')

   {

     cout<<"\n  Enter Item for Insertion\n";

     cin>>Item;

     res=Insert(Queue,Item);

     if(res==-1)

       {

     cout<<"Overflow \n";exit(1);

    }

      cout<<"\n Now the Queue(front....to....rear)is: \n";

      Display(Queue,front,rear);

      cout<<"\n Want to insert more elements?(y|n)...";

      cin>>ch;

   }

     cout<<"Now deletion of elements begins,,,\n";

     ch='Y';

     while(ch=='y'||ch=='Y')

     { res=Remove(Queue);

       if( res==-1)

       {cout<<"Underflow!!!Aborting!!\n";   exit(1);

       getch();

       }

       else

       {  cout<<"\n Element deletion is: "<<res<<endl;

      cout<<"now the Queue(front...to...back) begins:";

      Display(Queue,front,rear);

       }

       cout<<"\nwant to delete more elements ?(y/n)....\n";cin>>ch;

     }

     return 0;

  }//main end

  int Insert(int Queue[], int ele)

  {

     if(rear == size-1) return -1;

     else

     if(rear==-1)

     {

      front=rear=0;

      Queue[rear]=ele;

     }

     else

     {

    rear++;

    Queue[rear]=ele;

     }

     return 0;

   }

   int Remove(int Queue[])

   {

     int ret;

     if(front==-1) return -1;

     else

     {

       ret=Queue[front];

       if(front == rear) front=rear=-1;

       else

       front++;

     }

     return ret;

   }

  void Display(int SQueue[],int front,int rear)

  {

     if(front==-1) return;

     for(int i=front;i<rear;i++)

    cout<<Queue[i]<<"<-";

     cout<<Queue[rear]<<endl;

  }