Reverse linked list - Javascript

reverse.js

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

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

  add(val) {
    let node = new Node(val);
    if (this.head === null) {
      this.head = node;
    } else {
      let curr = this.head;
      while (curr.next !== null) {
        curr = curr.next;
      }
      curr.next = node;
    }
  }

  reverse() {
    // TODO: implement
  }

  print() {
    let curr = this.head;
    let str = "";
    while (curr !== null) {
      str += curr.val + " ";
      curr = curr.next;
    }
    console.log(str);
  }
}

let list = new LinkedList();
list.add(1);
list.add(2);
list.add(3);
list.add(4);
list.add(5);

console.log("Original list:");
list.print();

list.reverse();

console.log("Reversed list:");
list.print();