note 103495 added to function.explode

I have source like this: <?php // $topic_id defined from $_REQUEST['topic_id']; // $page defined from explode(';', $_REQUEST['topic_id']); if (isset($_REQUEST['topic_id'])) { $topic_id = $_REQUEST['topic_id']; list($topic_id, $page) = array_map('intval', array_pad(explode(';', $topic_query), 2, 0)); } ?> if i try open it form web browser with example: http://server.com/script.php?topic_id=3;4 still normal but if i try open with http://server.com/script.php?topic_id[]=3;4 it's found error: Notice: Array to string conversion ---- Server IP: 69.147.83.197 Probable Submitter: 125.163.164.142 ---- Manual Page -- http://www.php.net/manual/en/function.explode.php Edit -- https://master.php.net/note/edit/103495 Del: integrated -- https://master.php.net/note/delete/103495/integrated Del: useless -- https://master.php.net/note/delete/103495/useless Del: bad code -- https://master.php.net/note/delete/103495/bad+code Del: spam -- https://master.php.net/note/delete/103495/spam Del: non-english -- https://master.php.net/note/delete/103495/non-english Del: in docs -- https://master.php.net/note/delete/103495/in+docs Del: other reasons-- https://master.php.net/note/delete/103495 Reject -- https://master.php.net/note/reject/103495 Search -- https://master.php.net/manage/user-notes.php