hvad er der galtt med denne php kode

Hej,:)
hvad er der galt med denne php kode
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</head><body>
<?php session_start();
$link = mysql_connect("mysql3.000webhost.com", "a1120621_admin", "bøh");
mysql_select_db("a1120621_talk", $link);
if(empty($_POST['brugernavn']) || empty($_POST['kodeord']))
{
header("location. ");
exit;
}
else
{
$user = mysql_real_escape_string($_POST['brugernavn']);
$pass = mysql_real_escape_string($_POST['kodeord']);
$query = mysql_query("SELECT * FROM brugere WHERE brugernavn='".$user."' AND kodeord = '".$pass."' LIMIT 1") or die(mysql_error());
if(mysql_num_rows($query) == '1'))
{
$_SESSION['brugernavn'] = $_POST['brugernavn'];
header("location: indextjek_php_123456789987654321147852369951753456852___________________________________________________________________________________________________________tjek123456789987654321");
}
else
{
header("location. ");
exit;
}
}
?>
<?php $link = mysql_connect("mysql3.000webhost.com", "a1120621_admin", "bøh");
mysql_select_db("a1120621_talk", $link);
?><?php session_start();
$link = mysql_connect("mysql3.000webhost.com", "a1120621_admin", "bøh");
mysql_select_db("a1120621_talk", $link);
if(empty($_POST['brugernavn']) || empty($_POST['kodeord']))
{
header("location. ");
exit;
}
else
{
$query = mysql_query("SELECT * FROM brugere WHERE brugernavn='". $_POST['brugernavn'] ."'") or die(mysql_error());
if(mysql_num_rows($query) == '1'))
{
$row = mysql_fetch_array($query);
if($row['kodeord'] == $_POST['kodeord'])
{
$_SESSION['brugernavn'] = $_POST['brugernavn'];
header("location: /mylogin/indextjek_php_123456789987654321147852369951753456852___________________________________________________________________________________________________________tjek123456789987654321.php");
}
else
{
header("location. ");
exit;
}
}
else
{
header("location. ");
exit;
}
}
?>
</body></html>