//menu driven program of circular queue
#include<iostream.h>
#include<conio.h>
#include<process.h>
#define size 5
int front=-1,rear=-1;
void insert_CQ(int QUEUE[],int ELEMENT,int &front,int &rear)
{ if(rear==size-1)
rear=0;
  else
rear++;
  if(rear==front)
  { cout<<"\n Queue overflow";
exit(1);
  }
  QUEUE[rear]=ELEMENT;
  if(front==-1)
front++;
}
void delete_CQ(int QUEUE[],int &front,int &rear)
{ int value;
  if(front==-1)
  { cout<<"\n Queue underflow";
exit(1);
  }
  value=QUEUE[front];
  cout<<"\n Element to be deleted is :"<<value;
  if(front==rear)
front=rear=-1;
  else
  { if(front==size-1)
front=0;
else
front++;
  }
}
void display_CQ(int QUEUE[],int &front,int &rear)
{ if(front>=0)
  { if(front<=rear)
{ for(int p=front;p<rear;p++)
  cout<<QUEUE[p]<<"<--";
  cout<<QUEUE[rear];
}
else
{ for(int p=front;p<=size-1;p++)
  cout<<QUEUE[p]<<"<--";
for(p=0;p<rear;p++)
  cout<<QUEUE[p]<<"<--";
cout<<QUEUE[rear];
}
  }
}
void main()
{ clrscr();
  int ch,element,queue[20];
  l:
  cout<<"\n Press 1 for PUSHING"
<<"\n Press 2 for POPING"
<<"\n Press 3 for TRAVERSAL"
<<"\n Press 4 to EXIT\n";
  cout<<"\n Enter your choice:";
  cin>>ch;
  if(ch==4)
  { cout<<"\n THANK YOU";
exit(0);
  }
  else if(ch==1)
  { cout<<"\n Enter the element to be inserted:";
cin>>element;
insert_CQ(queue,element,front,rear);
goto l;
  }
  else if(ch==2)
  { delete_CQ(queue,front,rear);
goto l;
  }
  else
  { display_CQ(queue,front,rear);
goto l;
  }
  getch();
}