Circular Linked List (Advantages & Disadvantages)

What is a Circular Linked List?

A circular linked list is a sequence of nodes arranged in such a way that each node can be retraced to itself. Here a “node” is a self-referential element with pointers to one or two nodes in its immediate vicinity.

Below is a depiction of a circular linked list with 3 nodes.

circular linked nodes

Basic Operations in Circular Linked lists

The basic operations on a circular linked list are:

  1. Insertion
  2. Deletion and
  3. Traversal
  • Insertion is the process of placing a node at a specified position in the circular linked list.
  • Deletion is the process of removing an existing node from the linked list. The node can be identified by the occurrence of its value or by its position.
  • Traversal of a circular linked list is the process of displaying the entire linked list’s contents and retracing back to the source node.

Advantage of Circular linked list:

  • We can go to any node from any node in the Circular linked list which was not possible in the singly linked list if we reached the last node.
  • Easily we can go to head from the last node.
  • In a circular list, any node can be starting point means we can traverse each node from any point.
  • No requirement for a NULL assignment in the code. The circular list never points to a NULL pointer unless fully deallocated.

Disadvantages of Circular Linked List:

  • Circular lists are complex as compared to singly linked lists.
  • Reverse of circular list is a complex as compared to singly or doubly lists.
  • If not handled carefully, then the code may go in an infinite loop.
  • Harder to find the end of the list and loop control.
  • Inserting at Start, we have to traverse the complete list to find the last node. (Implementation Perspective)

Time Complexity: 

OPERATIONBEGINNINGENDOTHER POSITIONS
InsertionO(1)O(1)O(n)
DeletionO(1)O(n)O(n)

Space Complexity: O(1)

Special thanks to Ankit Kumar Das for contributing to this article on takeUforward. If you also wish to share your knowledge with the takeUforward fam, please check out this article