Online PHP editor | output for 4NNDn

<?php $lules = array( 'dsf1sdfd' => '', 'sdfd2sffffff' => 0, 'dfsdf3sdfefd' => 'fdsf', 'dsfsdf4d' => '', 'sdfdsff5ffff' => 0, 'dfsdfsdf6efd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', ); $rules = array( 'dsf1sdfd' => '', 'sdfd2sffffff' => 0, 'dfsdf3sdfefd' => 'fdsf', 'dsfsdf4d' => '', 'sdfdsff5ffff' => 0, 'dfsdfsdf6efd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', 'dsfsdfd' => '', 'sdfdsffffff' => 0, 'dfsdfsdfefd' => 'fdsf', ); $time = time(); foreach($lules as $key => $value) { if(empty($value)) { unset($lules[$key]); } } $time1 = time(); echo $time1 - $time; var_dump($lules); $time0 = time(); $bules = array_filter(&$rules); $time2 = time(); echo $time2 - $time0; var_dump($bules); var_dump($rules);