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|
#!perl
package Games::Word;
require Exporter;
@ISA = qw/Exporter/;
@EXPORT_OK = qw/random_permutation is_permutation all_permutations
shared_letters shared_letters_by_position
random_string_from
is_substring all_substrings
is_subpermutation all_subpermutations/;
use strict;
use warnings;
use Math::Combinatorics qw/factorial/;
use Test::Deep::NoTest;
sub random_permutation {
my $word = shift;
return '' if $word eq '';
my $letter = substr $word, int(rand length $word), 1, '';
return $letter . random_permutation($word);
}
sub is_permutation {
my @word_letters = split //, shift;
my @perm_letters = split //, shift;
return eq_deeply(\@word_letters, bag(@perm_letters));
}
sub _permutation {
my $word = shift;
my $perm_index = shift;
return '' if $word eq '';
my $len = length $word;
die "invalid permutation index" if $perm_index >= factorial($len) ||
$perm_index < 0;
use integer;
my $current_index = $perm_index / factorial($len - 1);
my $rest = $perm_index % factorial($len - 1);
my $first_letter = substr($word, $current_index, 1);
substr($word, $current_index, 1) = '';
return $first_letter . _permutation($word, $rest);
}
sub all_permutations {
my $word = shift;
my @ret = ();
push @ret, _permutation($word, $_)
for 0..(factorial(length $word) - 1);
return @ret;
}
sub shared_letters {
my @a = sort split //, shift;
my @b = sort split //, shift;
my @letters = ();
my ($a, $b) = (shift @a, shift @b);
while (defined $a && defined $b) {
if ($a eq $b) {
push @letters, $a;
($a, $b) = (shift @a, shift @b);
}
elsif ($a lt $b) {
$a = shift @a;
}
else {
$b = shift @b;
}
}
return @letters;
}
sub shared_letters_by_position {
my @a = split //, shift;
my @b = split //, shift;
my @letters = ();
while (my ($a, $b) = (shift @a, shift @b)) {
last unless (defined $a && defined $b);
if ($a eq $b) {
push @letters, $a;
}
else {
push @letters, undef;
}
}
return wantarray ? @letters : grep { defined } @letters;
}
sub random_string_from {
my ($letters, $length) = @_;
die "invalid letter list" if length $letters < 1 && $length > 0;
my @letters = split //, $letters;
my $ret = '';
$ret .= $letters[int rand @letters] for 1..$length;
return $ret;
}
sub is_substring {
my ($substring, $string) = @_;
return 1 if $substring eq '';
my $re = join('?', map { quotemeta } split(//, $string)) . '?';
return $substring =~ $re;
}
sub all_substrings {
my $string = shift;
return ('') if $string eq '';
my @substrings = ($string);
my $before = '';
my $current = substr $string, 0, 1, '';
while ($current) {
@substrings = (@substrings,
map { $before . $_ } all_substrings($string));
$before .= $current;
$current = substr $string, 0, 1, '';
}
return @substrings;
}
sub is_subpermutation {
my @subword = split //, shift;
my @word = split //, shift;
return eq_deeply(\@subword, subbagof(@word));
}
sub all_subpermutations {
return map { all_permutations $_ } all_substrings shift;
}
=head1 NAME
Games::Word - ???
=head1 VERSION
Version 0.01 released ???
=cut
our $VERSION = '0.01';
=head1 SYNOPSIS
use Games::Word;
do_stuff();
=head1 DESCRIPTION
=head1 SEE ALSO
L<Foo::Bar>
=head1 AUTHOR
Jesse Luehrs, C<< <jluehrs2 at uiuc.edu> >>
=head1 BUGS
No known bugs.
Please report any bugs through RT: email
C<bug-games-word at rt.cpan.org>, or browse
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Games-Word>.
=head1 SUPPORT
You can find this documentation for this module with the perldoc command.
perldoc Games::Word
You can also look for information at:
=over 4
=item * AnnoCPAN: Annotated CPAN documentation
L<http://annocpan.org/dist/Games-Word>
=item * CPAN Ratings
L<http://cpanratings.perl.org/d/Games-Word>
=item * RT: CPAN's request tracker
L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Games-Word>
=item * Search CPAN
L<http://search.cpan.org/dist/Games-Word>
=back
=head1 COPYRIGHT AND LICENSE
Copyright 2008 Jesse Luehrs.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
1;
|
