How to write PHP stack

Among the interview questions yesterday, there was a question about the application of stack. I knew the principle at that time, but I had not written the specific code. I will write about it today. .

<?php
/*
 * Created on 2015-4-9
 *
 * PHP栈的应用
 */

 class Stack{

 	private $stack_arr =array();
 	private $end = null;

 	public function push($str){

 		if($this->end === null){
 			$this->end = 0;
 		}else{
 			$this->end++;
 		}

 		$this->stack_arr[$this->end] = $str;

 	}

 	public function pop(){
		// if($this->end=null){return false;} //如果这样写，变量end为0的时候，是否就出错了
		if(empty($this->stack_arr)){return false;}
		  $pop_data = $this->stack_arr[$this->end];

		  array_splice($this->stack_arr,$this->end);

		 $this->end--;
		 return $pop_data;
	 	}

	 public function getData(){

	 	return $this->stack_arr;
	 }
 }
$arr = array();

$data_obj =new Stack();
$data_obj->push("1_one");
$data_obj->push("2_two");
$data_obj->push("3_three");
$data_obj->pop();
$arr = $data_obj->getData();
print_r($arr);


?>

Print results:
---------------------------------------- -------------------------------------------------- ---------------------
Array ( [0] => 1_one [1] => 2_two )

The above introduces how to write the PHP stack, including various aspects. I hope it will be helpful to friends who are interested in PHP tutorials.