http://www.perlmonks.org?node_id=78346


in reply to (Golf as well): List of Partitions

Here's one that is 65 characters, returns as array of arrays, but has duplicates (though the orders are unique).
sub P { $_[0]?map{my$c=$_;map[$c,@$_],P($_[0]-$c)}(1..$_[0]):[] }
Update: Same thing, but avoids repetitions: Total chars: 96
sub P { my$b=$_[1]||$_[0]; $_[0]?map{my$c=$_;map[$c,@$_],P($_[0]-$c,$c)}grep{$_<=$b}(1..$_[0]):[] }

Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

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Re (tilly) 2 (non-recursive): (Golf as well): List of Partitions
by tilly (Archbishop) on May 06, 2001 at 20:39 UTC
    The first is a non-solution in my books, but the second is very good. But I was wondering if it was possible to do a reasonable non-recursive solution, and at 87 by my count, 94 counting the body, it seems like the best so far.
    sub P{ $n=pop;@a=[0];map{$i=$_;push@{$a[$i+$_]},map[$i,@$_],@{$a[$_]}for 0..$n}1..$n;@{$a[$n]} }
    I keep on thinking this should be improvable, but darned if I can see it.