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

int diplay_menu();
class queue
{
  int arr[10];
  int front; // delete from this positionint rear;  // insert from this positionpublic:
     queue()
     {
      front=-1;
      rear=-1;
     }
     int getfront();
     int getrear();
     void insert(int);
     void delete_element();
     void rearrange();
     void display();
};


int diplay_menu()
{
 clrscr();
 int ch;
 cout<<endl;
 cout<<"\t\t\t| 1 | : Insert Element"<<endl;
 cout<<"\t\t\t| 2 | : Delete Element"<<endl;
 cout<<"\t\t\t| 3 | : Display Queue"<<endl;
 cout<<"\t\t\t| 4 | : Rearrange Queue"<<endl;
 cout<<"\t\t\t| 5 | : Exit"<<endl;
 cout<<"Enter Your Choice :";
 cin>>ch;
 return(ch);
}

int queue :: getfront()
{
 return(front);
}
int queue :: getrear()
{
 return(rear);
}
void queue :: insert(int x)
{
  arr[rear+1]=x;
  if(front==-1)
  {
   front=0;
  }
  rear=rear+1;
}




void queue :: delete_element()
{
 arr[front]=0;
 front=front+1;
 if(front>rear)
 {
  front=-1;
  rear=-1;
 }
}

void queue :: rearrange()
{
 if(front!=-1 && rear !=-1)
 {
  if(front!=0)
  {
   for(int i=0;i<=(rear-front);i++)
   {
     arr[i]=arr[front+i];
   }
  }
  rear=rear-front;
  front=0;
 }
}

void queue :: display()
{
 cout<<endl;
 if(front!=-1 && rear !=-1)
  {
    for(int i=front;i<=rear;i++)
    {
        cout<<"Queue["<<i<<"] :"<<arr[i]<<"\t";
    }
  }
 else
 {
  cout<<"Queue is empty !!!";
 }
}


void main()
{
 clrscr();
 queue q1;
 while(1)
 {
  switch(diplay_menu())
  {
   case 1: if(q1.getrear()==9)
       {
         if(q1.getfront()==0)
         {
          cout<<"Queue is Full !!!";
          getch();
          break;
         }
         else
         {
           char c;
           cout<<"There is a Space in a Queue"<<endl;
           cout<<"Do you want to Rearrange Queue [Y/N] ?";





           cin>>c;
           if(c=='y' || c=='Y')
           {
        q1.rearrange();
           }
           else
           {
        break;
           }
         }
       }
        int no;
        cout<<"Enter Number to insert :";
        cin>>no;
        q1.insert(no);
        q1.display();
        getch();
        break;
   case 2 : if(q1.getfront()!=-1 && q1.getrear() !=-1)
        {
         q1.delete_element();
        }
        else
        {
         cout<<"Queue is empty !!!"<<endl;
        }
        q1.display();
        getch();

        break;
   case 3 : q1.display();
        getch();
        break;
   case 4 : q1.rearrange();
        break;
   case 5 : exit(1);
  }
 }
}