Translate Perl Regular Expression?
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I am needing to obtain the algorithm used in this little bit of Perl code, but I know nothing about Perl.  Usually that's not a problem since I will research the language, but this regular expression stuff is way over my head!

Could anybody pseudo-code this?  I just need to know what's going on so I can implement it in something else, preferably PHP or even C++, but I'll worry about that part.  I just need to somehow decipher what this is doing:

    $a = $ARGV[0];
    $a =~ s/[^A-F0-9]+//simg;
    @b = reverse split /(\S{2})/,$a;
    $c = join "", @b;
    $c .= "0000";
    $d = hex($c) % 999999929;
    print "$d\n";