b-u bbb bbc bbn bbr bbu bcb bcc bcn bcr bcu bnb bnc bnn bnr bnu brb brn brr bru bub buc bun bur buu c-- cbb cbc cbn cbr cbu ccb ccc ccn ccr ccu cn- cnb cnc cnn cnr cnu crb crc crn crr cru cub cuc cun cur cuu nbb nbc nbn nbr nbu ncb ncc ncn ncr ncu nnb nnc nnn nnu nrb nrc nrn nrr nru nub nuc nun nur nuu rbb rbc rbn rbr rbu rcb rcc rcn rcr rcu rnb rnc rnn rnr rnu rrb rrc rrn rrr rru rub ruc run rur ruu ubb ubc ubn ubr ubu ucb ucc ucn ucr ucu un- unb unc unn unr unu ur- urb urc urn urr uru uuc uun uur uuu