ListNode.js

/**
 * ListNode 链表数据结构
 * @param val
 * @param next
 * @constructor
 */

class ListNode {
  constructor(val, next) {
    this.val = (val === undefined ? 0 : val);
    this.next = (next === undefined ? null : next);
  }

  static parse(arr) {
    if (arr.length === 0) {
      return null; // Return null for an empty array
    }
    const head = new ListNode(arr.shift(), null);
    let current = head;
    while (arr.length > 0) {
      current.next = new ListNode(arr.shift(), null);
      current = current.next;
    }
    return head;
  }

  static toArray(listNodes, arr = []) {
    if (listNodes === undefined || listNodes === null) {
      return arr;
    }

    arr.push(listNodes.val);
    return ListNode.toArray(listNodes.next, arr);
  }
}

module.exports = ListNode;