php-堆栈

//用数组来实现堆栈/*$stacklist = array();array_push($stacklist, "a");array_push($stacklist, "b");array_push($stacklist, "c");$data = array_pop($stacklist);var_dump($data);*//*  节点信息   */                            class node {public $value;   //节点的数据 function __construct($value) {$this->value = $value;}}/* 堆栈的实现*/                                                             class stack{public$last;  //指向尾部元素public  $stacklist; //堆栈元素列表private$size=0; //队列节点个数//出栈function pop( ){if($this->size == 0){return null;exit('error! the stack is empty!');}$data = $this->last;array_pop($this->stacklist);$this->last = end ($this->stacklist);$this->size--;return $data;}//入栈function push ($value ){$node=new node($value);$this->last = $node;$this->stacklist[] = $node;$this->size++;}//返回栈顶元素，但是不出栈function end(){//此处代码等你来完善}function size(){return $this->size;}}//以下开始是demo展示$stack = new stack();for ($j=0;$j<10; $j++){$stack ->push($j);}while( $node=$stack ->pop() ){echo $node->value, "\n";}