Well done! I too was trying to see how to remove the recursion,
without success.
Have you considered the (trivial) modification, to rename "r" as "a",
and "a" as something else, to allow easier comparison with your verb?
BTW, I'd be interested to see reactions to my offering of a "constructive"
approach, sent some time yesterday. I've complicated it somewhat in
slightly reducing the amount of redundancy necessitating filtering out
unsuitable rows, but won't trouble the forum with those changes yet,
if ever.
Also, apologies to you and Lippu Esa for getting your names wrong. My
lame excuse is that I was sending messages from iPad, re work on a laptop.
Mike
On 31/10/2017 09:23, Erling Hellenäs wrote:
parRuskey =: 4 : 0
r=. (i.y) S (x-1);y-1
r </."1 i.y
)
S =: 4 : 0
'k n' =. y
a=.x
r=. (0,_1{.$a)$0
if. k=n do.
r=.a
else.
for_i. i.k+1 do.
r=.r, (i n } a) S k;n-1
end.
if. k > 0 do.
r=.r, (k n } a) S (k-1);n-1
end.
end.
r
)
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