$id = md5(time().microtime()+$_SERVER['HTTP_USER_AGENT']);
	$i = 4;
	while($i<32){
		$i++;
		$k2 = substr($id,0,$i);
		$q = "SELECT count(id) FROM url where id = '$k2';";
		$res = $c->q($q);
		$fetch = mysql_fetch_array($res);
		if($fetch[0] == 0){
			$id = $k2;
			break;
		}
	}