@bKeyChars is being translated using ord() then translated back using chr(). The dashes can be added using a regex outside the first loop simplifying the outer loop. @bProductKey can be found without a need for @bDigitalProductID. The for loops can be rewritten to a more "perlish" style and we can step through @bProductKey without resorting to indexes. Finally, we can get rid of the Hungarian notation.
sub getXPkey {
my $key = shift;
my @encoded = ( unpack 'C*', $Registry->{$key} )[ reverse 52 .. 66
+ ];
# Get indices
my @indices;
foreach ( 0 .. 24 ) {
my $index = 0;
# Shift off remainder
( $index, $_ ) = quotient( $index, $_ ) foreach @encoded;
# Store index.
unshift @indices, $index;
}
# translate base 24 "digits" to characters
my $cd_key =
join '',
qw( B C D F G H J K M P Q R T V W X Y 2 3 4 6 7 8 9 )[ @indice
+s ];
# Add seperators
$cd_key =
join '-',
$cd_key =~ /(.{5})/g;
return $cd_key;
}
sub quotient {
use integer;
my( $index, $encoded ) = @_;
# Same as $index * 256 + $product_key ???
my $dividend = $index * 256 ^ $encoded;
# return modulus and integer quotient
return(
$dividend % 24,
$dividend / 24,
);
}
This makes for a little cleaner look, not a speed increase. I tend more toward clean, maintainable code than fast code.
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