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Doubly Linked List ready. Select an operation tab below.
Size:
3 / 7
Time:
O(1)Shortcuts: H Head • T Tail • F Find • D Delete • C Clear • M Sound • Z Focus
Implementation Code
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class DoubleNode<T> {
value: T;
next: DoubleNode<T> | null = null;
prev: DoubleNode<T> | null = null;
constructor(value: T) {
this.value = value;
}
}
class DoublyLinkedList<T> {
head: DoubleNode<T> | null = null;
tail: DoubleNode<T> | null = null;
size = 0;
insertHead(value: T): void {
const node = new DoubleNode(value);
if (!this.head) {
this.head = node;
this.tail = node;
} else {
node.next = this.head;
this.head.prev = node;
this.head = node;
}
this.size++;
}
insertTail(value: T): void {
const node = new DoubleNode(value);
if (!this.tail) {
this.head = node;
this.tail = node;
} else {
this.tail.next = node;
node.prev = this.tail;
this.tail = node;
}
this.size++;
}
delete(value: T): boolean {
let current = this.head;
while (current) {
if (current.value === value) {
if (current.prev) {
current.prev.next = current.next;
} else {
this.head = current.next;
}
if (current.next) {
current.next.prev = current.prev;
} else {
this.tail = current.prev;
}
this.size--;
return true;
}
current = current.next;
}
return false;
}
}Complexity Analysis
Access
O(n)
Search
O(n)
Insertion
O(1)
Deletion
O(1)
Space Complexity
O(n)
Color Legend
Primary Node (Top / Front / Head)
Inspected / Peeked
Element / Node
A Doubly Linked List is a linear data structure composed of sequentially linked nodes. Unlike a singly linked list, each node contains two pointers: one referencing the previous node and another referencing the next node. This allows full bidirectional traversal and O(1) removals when a pointer to a node is already available.