Write a program in C language to implement the insertion and deletion operations in a circular queue?

Answer 1

/* Circular Queues */
  #include<iostream.h>
  #include<conio.h>

  const int MAX = 5;
  class cqueue
  {
  int a[MAX],front,rear;
  public :
   cqueue()
     {
       front=rear=-1;
     }
     void insert(int );
     int deletion();
     void display();
  };

  void cqueue :: insert(int val)
  {
if((front==0 && rear==MAX-1) || (rear+1==front))
  cout<<" Circular Queue is Full";

else
{
   if(rear==MAX-1)
  rear=0;
   else
rear++;
   a[rear]=val;
}
if(front==-1)
   front=0;
  }
  int cqueue :: deletion()
  {
int k;
if(front==-1)
cout<<"Circular Queue is Empty";
else
{
k=a[front];
if(front==rear)
   front=rear=-1;
else
{
   if(front==MAX-1)
  front=0;
   else
  front++;
}
}
return k;
  }
  void cqueue :: display()
  {
  int i;
  if(front==-1)
cout<<"Circular Queue is Empty";
  else
  {
if(rear < front)
{
for(i=front;i<=MAX-1;i++)
   cout<<a[i]<<"   ";
for(i=0;i<=rear;i++)
   cout<<a[i]<<"   ";
}
else
{
for(i=front;i<=rear;i++)
   cout<<a[i]<<"   ";
cout<<endl;
}
  }
  }

  void main()
  {
cqueue c1;

int ch,val;
char op;
do
{
   clrscr();
   cout<<"-----------Menu-------------";cout<<endl;
   cout<<".....1.Insertion";cout<<endl;
   cout<<".... 2.Deletion:";cout<<endl;
   cout<<".....3.Display";cout<<endl;
   cout<<".... 4.Exit";cout<<endl;
   cout<<".....Enter Your Choice <1..4> ?"<<endl;
   cin>>ch;
   switch(ch)
   {
  case 1 : cout<<"Enter Element to Insert ?";
cin>>val;
c1.insert(val);
break;
  case 2 : val=c1.deletion();
cout<<"Deleted Element :"<<val<<endl;
break;
  case 3 : c1.display();
break;
}
cout<<"Do you want to continue<Y/N> ?"<<endl;
cin>>op;
  }while(op=='Y' || op=='y');
   getch();
}