Page 523 - Computer science 868 Class 12
P. 523

Step 6:  Accept cont
                 Step 7:  If cont=“Yes” or cont=“yes” then go to Step 3

                 Step 8:  Stop.
                 The algorithm for deletion operation in a circular queue is given below.

                 int dequeue(int qu[] , int max , int front , int rear)
                 Step 1:  Start.

                 Step 2:  If rear = front then display “Queue Underflow”, return value
                 Step 3:  Assign t=qu[front]

                 Step 4:  Assign front = (front+1)%max
                 Step 5:  Return t
                 Step 6:  Accept cont

                 Step 7:  If cont=“Yes” or cont=“yes” then go to Step 2
                 Step 8:  Stop.


                   Program 6     A  class  called  Cqueue  is  defined  to  perform  operations  on  a  Circular  queue.  The  class
                                 description is given below.
                                 Class name               :   Cqueue
                                 Data Members
                                 ele[]                    :   an array to hold integer elements
                                 cap                      :   to store the capacity of the array
                                 front                    :   to point to the index of the front
                                 rear                     :   to point to the index of the rear
                                 Member Functions
                                 Cqueue (int max)         :     constructor to initialise the data members cap=max, front=0,
                                                              rear=0 and create the integer array
                                 void enque(int v)        :     to add integers from the rear index if possible else display the
                                                              message “Queue full..overflow”
                                 int deque()              :     to remove  and  return element from the front, if array is
                                                              empty then return -999
                                 void display()           :   to display the elements present in the circular queue
                                 Specify  the  class  Cqueue  giving  details  of  the  constructor(int),  member  functions  void
                                 enque(int), int deque(), and void display().


                   1       import java.util.*;
                   2       class Cqueue

                   3       {
                   4           int ele[];
                   5           int cap, front,rear;

                   6           Cqueue(int max) //constructor

                   7           {



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