#!/usr/bin/perl

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

my @x=qw/x y z/;
my @y=@x;
$y[1]='u';
print Dumper \@x, \@y;

@x=( map [qw/x y z/], 1..3 );
@y=@x;
$y[1][1]='u';
print Dumper \@x, \@y;

__END__

##</code><code>##

$VAR1 = [
          'x',
          'y',
          'z'
        ];
$VAR2 = [
          'x',
          'u',
          'z'
        ];
$VAR1 = [
          [
            'x',
            'y',
            'z'
          ],
          [
            'x',
            'u',
            'z'
          ],
          [
            'x',
            'y',
            'z'
          ]
        ];
$VAR2 = [
          $VAR1->[0],
          $VAR1->[1],
          $VAR1->[2]
        ];