for (keys %matches) {
    my $ordered = join '', sort split //;
    $matches{$_} = [ grep {
        length($ordered) < length($_)
        ? 0
        : do {
            my $re = '^(.*?)'
                   . join('(.*)', map {quotemeta} split '')
                   . '(.*)$';
            $ordered =~ /$re/;
        };
    } keys %words];
}