Logic headache, please help.

Hi all, brief explanation: I'm building a select list, to exclude certain directories from a search (with Ht://dig). The structure is like this: <select name="exclude"> <option value="">All levels</option> <option value="/lv2/|/lv3/|/lv4/">Level 1</option> <option value="/lv1/|/lv3/|/lv4/">Level 2</option> <option value="/lv1/|/lv2/|/lv4/">Level 3</option> <option value="/lv1/|/lv2/|/lv3/">Level 4</option> </select> for four levels, where the option value should be all lv's except the current option level. I have a variable $maxlevels to count up to however many levels are required and I want to make this select list work based on the value of $maxlevels. How would you approach the building of the list? I was going to use a while loop or two, but I'm stuck at the point of creating the value "string" which should contain all the levels from 1 to $maxlevels except the current level. which would seem to require some sort of conditional "if $thislevel string is" type of approach, but I can't get my head round it. Anyone put me out of my misery? Thanks Tony