php实现双向队列 class Deque{ private $queue = []; public function addFirst($item) { return array_unshift($this->queue,$item); } public function addLast($item) { return array_…

<?php // 使对象可以像数组一样进行foreach循环 (Iterator迭代器) class Test implements Iterator { private $arr = []; // 索引游标 private $_key = 0; public function __construct(array $arr) { $t…

// 保存评论 public function saveComment($data) { Db::startTrans(); try{ //计算嵌套循环 $query = self::withTrashed()->order('rgt','desc'); $parent_id = $data['parent_id'] ?? 0; if…