php 数据结构之链表队列_PHP教程

php 数据结构之链表队列

2021-07-02 16:29xingjigongsi PHP教程

这篇文章主要介绍了php 数据结构之链表队列的相关资料,希望通过本文能帮助到大家，需要的朋友可以参考下

php 链表队列

实例代码：

				?

									class Queue{ 

									  private $last; 

									  private $first; 

									  private $oldfirst; 

									  private static $n=0; 

									  public function __construct(){ 

									    $this->last   = null; 

									    $this->first  = null; 

									    $this->oldfirst = null; 

									  } 

									  public function push($item){ 

									    $this->oldfirst = $this->last; 

									    $this->last = new Node(); 

									    $this->last->item = $item; 

									    $this->last->next = null; 

									    if(empty($this->first)){ 

									      $this->first = $this->last; 

									    }else{ 

									      $this->oldfirst->next = $this->last; 

									    } 

									    self::$n++; 

									  } 

									  public function pop(){ 

									    if(self::$n<0){ 

									      return null; 

									    } 

									    $item = $this->first->item; 

									    $this->first = $this->first->next; 

									    self::$n--; 

									    return $item; 

									  } 

									} 

									class Node{ 

									  public $item; 

									  public $next; 

									} 

									$Queue = new Queue(); 

									$Queue->push("a"); 

									$Queue->push("b"); 

									$Queue->push("c"); 

									echo $Queue->pop().PHP_EOL; 

									echo $Queue->pop().PHP_EOL; 

									echo $Queue->pop().PHP_EOL; 

									echo $Queue->pop().PHP_EOL;