How to use math in triggers

[Gothok]

Set ItemsFound = (ItemsFound + 1)

... how can i get the +1?!? in my trigger i only know how to do

Set Varible = Variable or
Set Variable[index] = Variable[index] ??? plz help

i don't even know the right variable

 

[ap0calypse]

I already explained this in a PM...

 

[defskull]

It's under "Arithmetic"