* @lc app=leetcode id=328 lang=javascript
* [328] Odd Even Linked List
* Definition for singly-linked list.
* function ListNode(val) {
var oddEvenList = function (head) {
if (!head || !head.next) return head;
let odd = dummyHead1.next;
let even = dummyHead2.next;
while (odd && odd.next && even && even.next) {
const oddNext = odd.next.next;
const evenNext = even.next.next;
odd.next = dummyHead2.next;