PHP 2차원 연관 배열 탐색 방법

<?php
	$arr = array(//定义外层数组
    "北京负责人"=>array(1,&#39;高某&#39;,&#39;A公司&#39;,&#39;北京市&#39;,&#39;(010)987654321&#39;,&#39;gm@Linux.com&#39;),//子数组1
    "上海负责人"=>array(2,&#39;洛某&#39;,&#39;B公司&#39;,&#39;上海市&#39;,&#39;(021)123456789&#39;,&#39;lm@apache.com&#39;),//子数组2
    "天津负责人"=>array(3,&#39;峰某&#39;,&#39;C公司&#39;,&#39;天津市&#39;,&#39;(022)24680246&#39;,&#39;fm@mysql.com&#39;),  //子数组3
    "重庆负责人"=>array(4,&#39;书某&#39;,&#39;D公司&#39;,&#39;重庆市&#39;,&#39;(023)13579135&#39;,&#39;sm@php.com&#39;)     //子数组4
    );

	foreach($arr as $key=>$arr_item){
		echo $key;	//取出数组的键
		echo "<pre class="brush:php;toolbar:false">";
			print_r($arr_item);	//$arr_item就是子数组了
		echo "