Comparing a variable against an array and outputting data from a directly proportiona

[psykx]

Comparing a variable against an array and outputting data from a directly proportional array I can't see why the code isn't working. I have tried echoing variables at almost all stages but I can't get my head around it.

This code populates the arrays.

PHP Code:

$sqlquery = "SELECT forum_name, forum_id FROM phpbb_forums";
$result = $db->sql_query($sqlquery);
$f_num = 0;
$forumid = array();
$forumname = array();
   while ( ($row = $db->sql_fetchrow($result)))
    {
    $forumid[$f_num] = $row["forum_id"];
    $forumname[$f_num] = $row["forum_name"];
    ++$f_num;
    }
$db->sql_freeresult($result); 


then another query is performed which is most of the output is generated. then this is the code that I'm having problems with

PHP Code:

            while ( $f_num > 0 )
            {
                if ( $row["forum_id"] == $forumid[$f_num] )
                {
                   $f_name = $forumname[$f_num];
                   $f_id_num = $f_num;
                }
                $f_num--;
            } 


This code needs to replace $row['forum_id'] with the correct variable from the $forumname[] array each time "while ( ($row = $db->sql_fetchrow($result)))" runs.

[phpBuddy]

in the first case $f_num is 0-5
in the second case $f_num is 5->1. Not = 0.

In my code below,
when $f_count is = 5, the indexes will be:
0,1,2,3,4

PHP Code:

<?php

// a new variable, that holds number of forumid
$f_count = count($forumid);

$f_num = 0;
while ( $f_num < $f_count )
            {
                if ( $row["forum_id"] == $forumid[$f_num] )
                {
                   $f_name = $forumname[$f_num];
                   $f_id_num = $f_num;
                }
                $f_num++;
            }

?>

[psykx]

a shorter way of doing the same is

PHP Code:

while ( $f_num >= 0 )
{
etc...
} 


this was part of the problem, cheers the next bit is going to be to get the while loop to change a different variable leaving $f_num intact for the next row.