I found the following quiz on G+, and decided to solve it with APL:
https://plus.google.com/108865431001865524379/posts/FKMrYkF6h3u
The solution I came up with was this:
(⍳N)⍪[1.5]{+/⍎¨⊃,/⍕¨⍳⍵}¨⍳N←400
This creates a table showing the number of pages, and the sum of the digits for that number of pages.
I was surprised that the program ran so slowly, taking almost a second to finish on my (pretty fast) computer.
I'll follow up with profiler results, but I was wondering of anyone can come up with a faster solution?
Regards,
Elias