Since the provided implementation is doing a directory search, you must simply ensure that the specific files in the directory do not change, and that you are sorting alphabetically each time.

After the resources information is set and associated with a room Reservation database and Domino Directory, you can search for the free time of a room and a resource, and schedule them for a meeting.

Directories aren't regular files but are accessed every time you list them or make them the current working directory, so exclude them in the search using a negation and the -type flag.