var insert = function(value, parent) {

  var node = { val: value };

​

  if (parent) {

    // Connect a node to the parent.

    parent.next = node;

  }

  return node;

}

​

var traverse = function(root, callback) {

  while (root) {

    if (callback) {

      callback(root);

    }

    root = root.next;

  }

}

​

var reverse = function(node, parent) {

  var result = parent || {};

  if (node) {

    var child = node.next;

    node.next = parent;

​

    result = reverse(child, node);

  }

​

  return result;

}

​

// Create a simple linked list, consisting of 5 nodes.

var root = insert(1);

var child = insert(2, root);

child = insert(3, child);

child = insert(4, child);

child = insert(5, child);

​

// Display the linked list.

traverse(root, function(node) { console.log(node.val); })