Howdy adolfo, welcome to the Monastery!
In general, you'll have better luck posting your question as a new top-level post in Seekers of Perl Wisdom. Also, while you're at it, please use <code> tags to format your code; see Writeup Formatting Tips for more.
Also: the particular solution to the "ordered combinations" problem here is a golfed solution, meaning that the aim was to use as few keystrokes as possible, at the expense of (among other things) readability, time and space complexity. Unless you're specifically interested in Perl golf, you're likely better off using a different solution.
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link
or How to display code and escape characters
are good places to start.