class DoublyLinkedList {
constructor(value) {
this.head = new Node(value);
this.tail = this.head;
this.length = 1;
}
append(value) {
const newNode = new Node(value);
newNode.prev = this.tail;
this.tail.next = newNode;
this.tail = newNode;
this.length++;
return this;
}
prepend(value) {
const newNode = new Node(value);
newNode.next = this.head;
this.head.prev = newNode;
this.head = newNode;
this.length++;
return this;
}
printList() {
const array = [];
let currentNode = this.head;
while (currentNode !== null) {
array.push(currentNode.value);
currentNode = currentNode.next;
}
return array;
}
insert(index, value) {
if (index >= this.length) {
return this.append(value);
}
const newNode = new Node(value);
const leaderNode = this.traverseToIndex(index-1);
const followingNode = leaderNode.next;
newNode.next = followingNode;
followingNode.prev = newNode;
newNode.prev = leaderNode;
leaderNode.next = newNode;
this.length++;
return this;
}
traverseToIndex(index) {
let currentNode = this.head;
for (let i=0; i<index; i++)
{
currentNode = currentNode.next;
}
return currentNode;
}
remove(index) {
if (index >= this.length) {
console.log("Index doesn't exist");
return;
}
const leaderNode = this.traverseToIndex(index-1);
const nodeToRemove = leaderNode.next;
leaderNode.next = nodeToRemove.next;
this.length--;
}
}
class Node {
constructor(value) {
this.value = value,
this.next = null,
this.prev = null
}
}
const myLinkedList = new DoublyLinkedList(10);
myLinkedList.append(5);
myLinkedList.append(16);
myLinkedList.prepend(1);
console.log(myLinkedList);
console.log(myLinkedList.printList());
myLinkedList.insert(1,333);
console.log(myLinkedList.printList());
myLinkedList.remove(2);
console.log(myLinkedList.printList());
