ルービックキューブをシャッフルしたい

cube_shuffle

#!/usr/bin/env perl
use strict;
use warnings;

my $count = shift || 20;

my @random     = qw/R R F F U U L D M/;
my $rate_2     = 0.3;
my $rate_prime = 0.3;
my @result;

for my $i (1..$count) {
    my $type;
    while (1) {
        $type = $random[int(rand(scalar @random))];
        $result[-1] or last;
        $result[-1] =~ /$type/ or last;
    }
    if (rand() < $rate_2) {
        $type .= '2';
    }
    if ($type =~ /M/) {
        $type .= q{'};
    } elsif (rand() < $rate_prime) {
        $type .= q{'};
    }
    push @result, $type;
}

print join(' ', @result) . "\n";