use strict;

use Data::Dumper;

my %first;
$first{'foo'}{'bar'} = 1;
$first{'foo'}{'baz'} = 2;
$first{'bah'}{'oof'} = 3;

print "First hash:\n";
print Dumper \%first;

my %second = %first;
print "\nSecond hash\n";
print Dumper \%second;

print "\nFirst nested hash address: $first{'foo'}\n";
print "Second nexted hash address: $second{'foo'}\n";


##</code><code>##

First hash:
$VAR1 = {
          'bah' => {
                     'oof' => 3
                   },
          'foo' => {
                     'baz' => 2,
                     'bar' => 1
                   }
        };

Second hash
$VAR1 = {
          'bah' => {
                     'oof' => 3
                   },
          'foo' => {
                     'baz' => 2,
                     'bar' => 1
                   }
        };

First nested hash address: HASH(0x804ee40)
Second nexted hash address: HASH(0x804ee40)