one more question from same tutorial, can you do below in reference hash? 
my %histogram;
    $histogram{$_}++ for @list;

[download]
I was trying 
foreach (@data1) {
      $hist{$_}++ for $_;
}

my @uni = keys %hist;

print "@uni\n";

[download]
but above actually prints out the reference address. I tried few different things but does not print out the actual value.. can someone give me a pointer on this(no pun intended).. thanks. for example like below.... 
#!/usr/bin/perl -w

use strict;
use warnings;

use Data::Dumper;

my $ref = {
      a => { A => 1, B => 2, C => 3},
      b => { D => 1, E => 2, F => 4},
      c => { G => 2, H => 1, I => 2},
};

#print Dumper($ref);


my %hist;

foreach ($ref) {
    $hist{$_}++ for $_;
}

my @uni = keys %hist;

print "@uni\n";

[download]

In reply to Re^2: perl sort issue while going through article at perl.com by convenientstore
in thread perl sort issue while going through article at perl.com by convenientstore

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