http://qs1969.pair.com?node_id=482000


in reply to Algorithm for cancelling common factors between two lists of multiplicands

$i{$_}++ for (@a);
$i{$_}-- for (@b);

@c=grep { $i{$_} > 0 } keys @a;
@d=grep { $i{$_} < 0 } keys @b;

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btw, are your sample solution arrays right?

In Section Seekers of Perl Wisdom