Trigger Help

[g0dsmonkey]

I need help with a trigger. Here is wat the trigger is so far:

-Events
A unit enters regionX
-Contiditions
((Triggering unit) has itemX) equal to true
-Actions
Move itemX to (center of variableY[(random integer number between 1 and 16)])

How do i then remove the randomly selected integer from variableY ?! is it possible? thnks alot.

I hope it makes sense. Say if it doesnt! :fwink