This is a variant of the progressive index-of problem.
http://www.jsoftware.com/jwiki/Essays/Progressive%20Index-Of
Comparing the two "less"es:
[ {~ i...@#@[ -. i. NB. ordinary dyad -.
[ {~ i...@#@[ -. pi NB. "less" required here
----- Original Message -----
From: June Kim <[email protected]>
Date: Saturday, April 17, 2010 7:01
Subject: [Jprogramming] remove elements (with repetition allowed)
To: Programming forum <[email protected]>
> How would you implement "takeout"(Less with equally valued cell
> numberssignificant) in the following test cases?
>
> assert 1 2 -:&(/:~) 1 2 3 takeout 3
> assert (,:1) -:&(/:~) 1 1 1 takeout 1 1
> assert 1 3 4 -:&(/:~) 1 2 3 4 1 1 takeout 1 2 1
> assert 1 2 3 -:&(/:~) 1 2 3 3 2 takeout 3 2
>
> My first quick implementation(without much thought):
>
> keyind=:([:< i...@# ,. ])/.~
> takeout =: {:"1...@-.&(;@:keyind)
>
> I would appreciate simpler and more elegant solutions.
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