Queue Implementation Using Linked List in DSA C - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a queue in data structures?

A queue is a collection where elements are added at the back and removed from the front, following First-In-First-Out (FIFO) order.

beginner

Why use a linked list to implement a queue?

A linked list allows dynamic memory use and easy insertion/removal without shifting elements, making it efficient for queue operations.

beginner

What are the main operations in a queue implemented with a linked list?

The main operations are enqueue (add to back), dequeue (remove from front), and peek (view front element).

beginner

How do you check if a linked list queue is empty?

Check if the front pointer (head) is NULL. If it is NULL, the queue is empty.

intermediate

What happens to the rear pointer when the last element is dequeued from a linked list queue?

Both front and rear pointers are set to NULL because the queue becomes empty.

In a linked list queue, where is the new element added?

A At the rear (end) of the list

B At the front (start) of the list

C In the middle of the list

D It replaces the front element

New elements are added at the rear to maintain FIFO order.

What does the dequeue operation do in a linked list queue?

A Removes the element at the rear

B Adds a new element at the rear

C Adds a new element at the front

D Removes the element at the front

Dequeue removes the front element to follow FIFO.

How do you know if a linked list queue is empty?

A Rear pointer is NULL

B Both front and rear pointers are not NULL

C Front pointer is NULL

D Queue size is greater than zero

If the front pointer is NULL, the queue has no elements.

What happens to the rear pointer when the last element is dequeued?

A It is set to NULL

B It remains unchanged

C It points to the next element

D It points to the front

When the queue becomes empty, rear is set to NULL.

Which data structure is best suited for dynamic queue implementation?

A Array

B Linked List

C Stack

D Binary Tree

Linked lists allow dynamic size and efficient enqueue/dequeue.

Explain how enqueue and dequeue operations work in a queue implemented using a linked list.

Think about where new nodes are added and removed.

Describe how to check if a linked list queue is empty and what changes when the last element is removed.

Focus on the pointers that track the queue ends.