PHPの3次元配列を2次元配列に変換する方法

<?php
    $result = Array(0 => Array(0 => Array(bid => 41,brealname => &#39;we教官&#39;,cid => 41,crealname => &#39;we教官&#39;)),
                    1 => Array(0 => Array(bid => 6,brealname => &#39;虎子&#39;,cid => 19,crealname => &#39;张鱼&#39;))
    );
    //原数组
    print_r($result);
    echo "<br />";
    //第一种方法：
    foreach ($result as $key =>$v){
        $new_arr[]=$v[0];
    }
    echo &#39;<pre class="brush:php;toolbar:false">&#39;;
    print_r($new_arr);
    //第二种方法
    //初始化$arr2  
    $arr2=array();  
           
    //循环遍历三维数组$arr3  
    foreach($result as $value){  
        foreach($value as $v){  
             $arr2[]=$v;  
        }  
    }
    
    //销毁$arr3 
    unset($result,$value,$v);
    echo "<br /s>";
    echo "第二种方法：";
    echo &#39;<pre class="brush:php;toolbar:false">&#39;;
    print_r($arr2);
?>