I forgot to mention something else:

5) Don't try to parse html with your own regexes. There are plenty of perl HTML parsers that do the hard work for you. Here is one example:

use strict; 
use warnings; 
use 5.012;

use HTML::TreeBuilder;

my $string = <<END_OF_HTML;
<ul>
  <li>
    <div id="Show1400">
      <a href="../../../KeyboardKeys/RetainerClip/Acer/Aspire/1400">14
+00</a>
    </div>
  </li>
  <li>
    <div id="Show1410">
      <a href="../../../KeyboardKeys/RetainerClip/Acer/Aspire/1410">14
+10</a>
    </div>
  </li>
END_OF_HTML

#Note the missing </ul> tag above.

my $tree = HTML::TreeBuilder->new();
$tree->parse_content($string);

my @links = $tree->look_down('_tag', 'a'); 

for my $link (@links) {
    say $link->attr('href');
}

--output:--
../../../KeyboardKeys/RetainerClip/Acer/Aspire/1400
../../../KeyboardKeys/RetainerClip/Acer/Aspire/1410
[download]

The docs on how to use HTML::TreeBuilder are at HTML::Tree::Scanning.