@values = qw( 00 11 22 33 );
use Data::Dumper;
print Dumper \@values;
# generates the output:
$VAR1 = [
          '00',
          '11',
          '22',
          '33'
        ];

##</code><code>##

$values[6] = "66";
print Dumper \@values;
# generates the output:
$VAR1 = [
          '00',
          '11',
          '22',
          '33',
          undef,
          ${\$VAR1->[4]},
          '66'
        ];

##</code><code>##

$values[4] = "44";
 print Dumper \@values;
# generates the output
$VAR1 = [
          '00',
          '11',
          '22',
          '33',
          '44',
          undef,
          '66'
        ];

##</code><code>##

$values[1] = undef;
print exists $values[1];
# generates the output: 1, i.e., the array slot contains the value 'undef'.

##</code><code>##

delete $values[1];
delete $values[3];
print Dumper \@values;
# generates the output:
$VAR1 = [
          '00',
          undef,
          '22',
          ${\$VAR1->[1]},
          '44',
          ${\$VAR1->[1]},
          '66'
        ];

##</code><code>##

$values[6] = undef
print Dumper \@values;
# generates the output :
$VAR1 = [
          '00',
          undef,
          '22',
          ${\$VAR1->[1]},
          '44',
          ${\$VAR1->[1]},
          undef
        ];

##</code><code>##

$values[0] = undef;
$values[2] = undef;
$values[4] = undef;
print Dumper \@values;
# generates the output :
$VAR1 = [
          undef,
          undef,
          undef,
          ${\$VAR1->[1]},
          undef,
          ${\$VAR1->[1]},
          undef
        ];

$values[1] = undef
$values[3] = undef
$values[5] = undef
print join( "\n", \$values[0], \$values[1], \$values[2],                
                  \$values[3], \$values[4], \$values[5], 
                  \$values[6] );
# generates the output :
SCALAR(0x8279dd4)
SCALAR(0x81d64e0)
SCALAR(0x8279d50)
SCALAR(0x81d6294)
SCALAR(0x8279d38)
SCALAR(0x81d627c)
SCALAR(0x8279e10)


##</code><code>##

delete @values[0];
delete @values[1];
delete @values[2];
delete @values[3];
delete @values[4];
delete @values[5];
delete @values[6];
print Dumper \@values;
# generates the output :
$VAR1 = [];