Can't get this working

[Dark Jim]

I've attached the file here. This part is causing trouble:

PHP Code:

$expneed = 50;
$expaddedneed = 0;
$tempexp = $exp;

while ($tempexp > 0)
{
  $tempexp - $expneed;
  $expaddedneed = $expaddedneed + 25;
  if (($tempexp == 0) || ($tempexp > 0))
    {$level++;}
  $expneed = $expneed + $expaddedneed;
} 


When I enter a value for exp that is not 0 then it doesn't work because I get a connection timed out every time. What am I doing wrong?

Also can anyone help making this part a little more efficient?

PHP Code:

$lastuserid=$DB_site->query_first("SELECT MAX(userid) AS lastuser FROM user");

echo "<tr class='".getrowbg()."' valign='top'><td>";

$counter = 1;
while ($counter != ($lastuserid['lastuser']+1))
  {$someuser=$DB_site->query_first("SELECT username FROM user WHERE userid=$counter"); 
  if ($someuser[username]!="") {
    echo "<a href=\"rpgadmin.php?action=edituser&ausername=$someuser[username]\">$someuser[username]</a><br>";
    } 
  $counter++;
  }

echo "</td></tr>";