One of the fastest ways would be to use a math library like PARI. It uses very good primality tests internally. I don't have it installed right now, but you should be able to use:
use Math::Pari 'isprime';
my $num = shift || '12345678901';
print isprime($num) ? "$num is prime!\n"
: "$num is composite!\n";
Even if you are looking for the practice of implementing a nice primality test by hand, pari would be a good tool, as it supports all sorts of abstract algebra things (including fast modular arithmetic). If you want to do even that by hand, the above FAQ lists several primality test algorithms that you can use as starting points.
-
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>
<u> <ul>
-
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
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|