prev next problems

[HalfLife]

Gah....
I have this code in my page:

<?php
if ($_GET['page_num'] != 1){
  print ("<a href=\"tut_self.php?total_pages=".$_GET['total_pages']."&page_num=".$_GET['page_num']--."\">Previous</a>");
}
print (" - ");
if ($_GET['page_num'] != $_GET['total_pages']){
  print ("<a href=\"tut_self.php?total_pages=".$_GET['total_pages']."&page_num=".$_GET['page_num']++."\">Next</a>");
}
?>

The problem is;
the 'Previous' button links to the same page ($page_num stays the same), and the 'Next' button links to the previous page ($page_num is substracted by 1).
What the hell is going on here???
O_o

[TheIceman5]

dont double post lamer.

[HalfLife]

Thank you, that helped.

[harlowhair]

doing the calculations before creating the links e.g.

if [next link clicked]
pagenum++;
<a href....etc.

the ++ operator is evaluated after the expression so this may be yr problem.