// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/work-with-nodes-in-a-linked-list

var Node = function (element) {
  this.element = element;
  this.next = null;
};
var Kitten = new Node("Kitten");
var Puppy = new Node("Puppy");

Kitten.next = Puppy;
// Only change code below this line
const Cat = new Node("Cat");
Puppy.next = Cat;
const Dog = new Node("Dog");
Cat.next = Dog;