Thanks, fascinating ...

...but maybe I was not still not clear enough! ;-)

I'd rather prefer a solution better (readable | self documenting | maintainable) then

  DB<140> \%h
 => { a => 1, b => 2, c => 1, d => 2, e => 3 }

  DB<141> push @{ $h2{$h{$_}} }, $_ for keys %h
 => ""

  DB<142> \%h2
 => { 1 => ["c", "a"], 2 => ["b", "d"], 3 => ["e"] }

[download]

so not necessarily a complicated solution only relying on List::Util or List::MoreUtils ...

BUT I know that you love this kind of games ... ;D

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re^4: inverting hash / grouping values by LanX
in thread inverting hash / grouping values by LanX

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