class Node {
  constructor(val) {
    this.val = val;
    this.next = null;
  }
}

class LinkedList {
  constructor() {
    this.head = null;
  }

  append(val) {
    let newNode = new Node(val);
    if (!this.head) {
      this.head = newNode;
      return;
    }
    let current = this.head;
    while (current.next) {
      current = current.next;
    }
    current.next = newNode;
  }

  reverse() {
    let prev = null;
    let current = this.head;
    while (current) {
      let next = current.next;
      current.next = prev;
      prev = current;
      current = next;
    }
    this.head = prev;
  }

  printList() {
    let current = this.head;
    let output = '';
    while (current) {
      output += current.val + ' -> ';
      current = current.next;
    }
    console.log(output + 'null');
  }
}

// Example usage
let ll = new LinkedList();
ll.append(1);
ll.append(2);
ll.append(3);
console.log('Original List:');
ll.printList();
ll.reverse();
console.log('Reversed List:');
ll.printList();

Meta AI Response: 😎 Here's how you can reverse a linked list in JavaScript: class Node { constructor(val) { this.val = val; this.next = null; } } class LinkedList { constructor() { this.head = null; } append(val) { let newNode = new Node(val); if (!this.head) { this.head = newNode; return; } let current = this.head; while (current.next) { current = current.next; } current.next = newNode; } reverse() { let prev = null; let current = this.head; while (current) { let next = current.next; current.next = prev; prev = current; current = next; } this.head = prev; } printList() { let current = this.head; let output = ''; while (current) { output += current.val + ' -> '; current = current.next; } console.log(output + 'null'); } } // Example usage let ll = new LinkedList(); ll.append(1); ll.append(2); ll.append(3); console.log('Original List:'); ll.printList(); ll.reverse(); console.log('Reversed List:'); ll.printList(); This code defines a LinkedList class with methods to append nodes, reverse the list, and print the list. The reverse method uses a standard three-pointer approach to reverse the links between nodes. 💡 Do you want me to explain any part of this code or help with a variation of this problem?