b-u bbb bbc bbn bbt bbu bcb bcc bcn bct bcu bnb bnc bnn bnt bnu btb btc btn btt btu bub buc bun but buu c-- cbb cbc cbn cbt cbu ccb ccc ccn cct ccu cn- cnb cnc cnn cnt cnu ctb ctc ctn ctt ctu cub cuc cun cut cuu nbb nbc nbn nbt nbu ncb ncc ncn nct ncu nnb nnc nnn nnt nnu ntb ntc ntn ntt ntu nub nuc nun nut nuu tbb tbc tbn tbt tbu tcb tcc tcn tct tcu tnb tnc tnn tnt ttb ttc ttn ttt ttu tub tuc tun tut tuu ubb ubc ubn ubt ubu ucb ucc ucn uct ucu un- unb unc unn unt unu utb utc utn utt utu uuc uun uut uuu