PROGRAM FOR QUEUE (INSERTION & DELETION)

#include<iostream.h>
#include<conio.h>
#include<stdio.h>
#include<process.h>
# define size 5


class queue
{
  int front,rear,a[size];
  public:

  queue()
  {
    front=0;rear=0;
  }
  void addQ(int item)
  {
    if(rear==size)
       cout<<"Queue is full"<<endl;
    else
       a[rear++]=item;
  }
  void delQ(int item)
  {
    if(front==rear)
    {
       cout<<"Queue is empty"<<endl;
    }
    else
    {
a[front++];
    }
  }
  void display()
  {
    int i;
    if(front==rear)
    {
      cout<<"\n Queue is empty";
      getch();
      return;
    }
    for(i=front+1;i<=rear;i++)
      cout<<a[i]<<"\t";
  }
};

void main()
{
  queue q1;
  int item;
  clrscr();
  int choice;
  do
  {
    clrscr();
    cout<<endl<<"Main menu";
    cout<<endl<<"1.Add\t 2.Delete\t 3.Display\t 4.Quit\t";
    cout<<endl<<"Enter ur choice:";
    cin>>choice;
    switch(choice)
    {
      case 1:cout<<endl<<"Enter an element to add:";
    cin>>item;
    q1.addQ(item);
    break;
      case 2:cout<<endl<<"Enter an element to delete:";
    cin>>item;
    q1.delQ(item);
    break;
      case 3:q1.display();
    break;
      case 4:exit(0);
    }
    getch();
   }while(1);
}