php双向队列

<?php ????class Deque{ ???????public $queue = array(); ???????/** ????????* 尾部入对 ????????* @param [type] $value [description] ????????*/ ???????public function addLast($value){ ???????????return array_push($this->queue,$value); ???????} ???????/** ????????* 尾部出队 ????????* @return [type] [description] ????????*/ ???????public function removeLast(){ ???????????return array_pop($this->queue); ???????} ???????/** ????????* 头部入队 ????????* @param [type] $value [description] ????????*/ ???????public function addFirst($value){ ???????????return array_unshift($this->queue, $value); ???????} ???????/** ????????* 头部出队 ????????* @return [type] [description] ????????*/ ???????public function removeFirst(){ ???????????return array_shift($this->queue); ???????} ???????/** ????????* 清空队列 ????????* @return [type] [description] ????????*/ ???????public function makeEmpty(){ ???????????unset($this->queue); ???????} ???????/** ????????* 获取列头 ????????* @return [type] [description] ????????*/ ???????public function getFirst(){ ???????????return reset($this->queue); ???????} ???????/** ????????* 获取列尾 ????????* @return [type] [description] ????????*/ ???????public function getLast(){ ???????????return end($this->queue); ???????} ???????/** ????????* 获取长度 ????????* @return [type] [description] ????????*/ ???????public function getLength(){ ???????????return count($this->queue); ???????} ???}