Quick question about recipes

All I need to know is how to detect multiple instances of an item (ie: Item A, Item A, Item B) for a recipe. I had a working trigger but I seemed to have forgotten...

theres a quick way for mutltiple items that are different, and a way for items of the same type for different times all you have to do is:

event
unit aqauires an item
conditions
item type of item caried by hero manipulating item of type "bow" equal to type "bow"
item type of item caried by hero manipulating item of type "arrows" equal to type "arrows"
actions
remove item caried by hero manipulating item of type "bow"
remove item caried by hero manipulating item of type "arrows"
create i"bow and arrrows" for hero manipulating item

for multiple items
the other way is to run a for loop:
for loop integer a
if item in slot interger a
blah
blah
blah

basically the goal is to find the item in slot integer a, then once its found it you run another for loop and find the other item of the same type thats not in the same slot