G'day LanX,

Here's a couple more to throw into the mix for you to reject. :-) 

#!/usr/bin/env perl

use strict;
use warnings;

my %h = (a => 1, b => 2, c => 1, d => 2, e => 1, f => 2);
my %i; $i{$h{$_}}[@{ $i{$h{$_}} }] = $_ for keys %h;
my %j = do { $_{$h{$_}}[@{$_{$h{$_}}}] = $_ for keys %h; %_ };

use Data::Dump;
dd \%h, \%i, \%j;

[download]

Output:

$ pm_hash_invert.pl
(
  { a => 1, b => 2, c => 1, d => 2, e => 1, f => 2 },
  { 1 => ["a", "e", "c"], 2 => ["f", "b", "d"] },
  { 1 => ["a", "e", "c"], 2 => ["f", "b", "d"] },
)

[download]

-- Ken

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

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