use Math::Combinatorics;
for (`cat /usr/share/dict/words`)
{   
    chomp;
    $real_words{$_}++
}   

while (<STDIN>)
{   
    chomp;
    my @letters = split //;
    foreach my $word_len (1 .. @letters)
    {   
        foreach my $combination (combine($word_len, @letters))
        {   
            foreach my $permutation (permute(@$combination))
            {
                    my $word = join '', @$permutation;
                    print "$word\n" if $real_words{$word};
            }
        }   
    }   
}
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