A hash of hashes (HoH) 
#! /usr/perl/bin

use warnings;
use strict;
use Data::Dumper;

my $abc = {
  one => {
    oneone => 11,
    onetwo => 12,
  },
  two => {
    twoone => 21,
    twotwo => 22,
  }
};

foreach my $key (keys %{$abc}) {
    if ( ref $abc->{$key} eq 'HASH' ) {
      for my $subkey (keys %{$abc->{$key}}){
        printf qq{%s -> %s\n}, $subkey, $abc->{$key}{$subkey};
      }
    }
}

[download]
onetwo -> 12
oneone -> 11
twotwo -> 22
twoone -> 21

[download]

In reply to Re: What data structure is this code looking for by wfsp
in thread What data structure is this code looking for by mhearse

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