Algorithm for inserting an element in circular queue
Procedure: CQINSERT (F, R, Q, N, Y)
- This procedure inserts Y at Rear end of the Circular Queue.
- Queue is represented by a vector Q containing N elements.
- F is pointer to the Front element of a queue.
- R is pointer to the Rear element of a queue.
1. [Reset Rear Pointer]
If R = N
Then R <-- 1
Else R <-- R+1
2. [Overflow?]
If F=R
Then Write ('Overflow')
Return
3. [Insert element]
Q[R] <-- Y
4. [Is Front pointer properly set?]
If F=0
Then F<--1
Return
Algorithm for deleting an element from circular queue
Function CQDELETE (F, R, Q, N)
- This function deletes & returns an element from Front end of the Circular Queue.
- Queue is represented by a vector Q containing N elements.
- F is pointer to the Front element of a queue.
- R is pointer to the Rear element of a queue.
1. [Underflow?]
If F = 0
Then Write (‘UNDERFLOW’)
Return(0)
2. [Delete Element]
Y <-- Q[F]
3. [Queue Empty?]
If F = R
Then F <-- R <-- 0
Return(Y)
4. [Increment Front Pointer]
If F=N
Then F<--1
Else F<--F+1
Return(Y)
