my @array;

$array[4] = 0;
print "   Set element 4: last at $#array\n";

$array[2] = undef;
delete $array[4];
print "Delete element 4: last at $#array\n";
delete $array[2];
print "Delete element 2: last at $#array\n";


##</code><code>##

   Set element 4: last at 4
Delete element 4: last at 2
Delete element 2: last at -1

##</code><code>##

use strict;
use warnings;

use strict;
use Data::Dump ('dump');
my $listref = ['a','b','c','d','e'];
@$listref = @{$listref}[0, 2, 4];
print "@$listref\n";