Aai wrote:
> e.g. is it possible to avoid 'some' boxing.
I responded:
> Oh! Sure.
The final form of the solution I posted to RC is:
hc10kE =: 1 1 , exp...@tail
expand =: 2+I.@;
tail =: copies&.>^:(<@>:`(<@,@2:))
copies =: >: |.@(#!.1 |.)~ 1 j. #;.1 #^:_1 ::1:~ ]~:{.
I added it as an "alternative solution", noting that while it is slightly
more complex, it is exponentially faster. Should I post the "true
recursive" ($:) formulation as well?
-Dan
PS: I find it appealing that "copies" is a showcase for all the features of
# : tally, copy in its full generality (i.e. with complex arguments), and
expand, with fit even. The verb is also a good way to understand how expand
differs from complex copy, and when you'd choose one over the other.
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