# 10.6: Circular queue

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Operations on Circular Queue:

• qInsert(value) This function is used to insert an element into the circular queue. In a circular queue, the new element is always inserted at Rear position.Steps:
1. Create a new node dynamically and insert value into it.
2. Check if front==NULL, if it is true then front = rear = (newly created node)
3. If it is false then rear=(newly created node) and rear node always contains the address of the front node.
• qRemove() This function is used to delete an element from the circular queue. In a queue, the element is always deleted from front position.Steps:
1. Check whether queue is empty or not means front == NULL.
2. If it is empty then display Queue is empty. If queue is not empty then step 3
3. Check if (front==rear) if it is true then set front = rear = NULL else move the front forward in queue, update address of front in rear node and return the element.

Here is an example of inserting and removing a few values with a circular queue This is the same as the non-circular EXCEPT that you must update the rear->next value to point to the head when you qRemove(), and set the new rear->next when you qInsert().

This page titled 10.6: Circular queue is shared under a CC BY-SA license and was authored, remixed, and/or curated by Patrick McClanahan.