A circular linked list can have only one reference direction (as with a linked list) or a double reference (as with a doubly linked list). The only difference between a circular linked list and a linked list is that the last element's next (tail.next) pointer does not make a reference to undefined, but to the first element (head), as we can see in the following diagram:
A doubly circular linked list has tail.next pointing to the head element, and head.prev pointing to the tail element:
Let's check the code to create the CircularLinkedList class:
CircularLinkedList extends LinkedList {
constructor(equalsFn = defaultEquals) {
super(equalsFn);
}
}The CircularLinkedList class does not need any additional properties, so we can simply extend the LinkedList class and overwrite the required methods to apply the special behavior.
We will overwrite the implementation of the insert and removeAt methods in the following topics.