Programming puzzles: processing lists!

[pier4r]

David thanks for your posts!

Please provide also the rest of the challenges otherwise I challenge myself (not bad, but still).

About the post #24 . As I wrote, if one writes helper functions to work on list in a general way (and not, say, only considering 3s and 5s) then it is fine.

Said that, Is the code that you pasted the helper function that should be called SUB!? I don't understand how is that routine used.