b-u bbb bbc bbn bbs bbt bbu bcb bcc bcn bcs bct bcu bnb bnc bnn bns bnt bnu bsb bsc bsn bss bst bsu btb btc btn bts btt btu bub buc bun bus but buu c-- cbb cbc cbn cbs cbt cbu ccb ccc ccn ccs cct ccu cn- cnb cnc cnn cns cnt cnu csb csc csn css cst csu ctb ctc ctn cts ctt ctu cub cuc cun cus cut cuu nbb nbc nbn nbs nbt nbu ncb ncc ncn ncs nct ncu nnb nnc nnn nns nnt nnu nsb nsc nsn nss nst nsu ntb ntc ntn nts ntt ntu nub nuc nun nus nut nuu sbb sbc sbn sbs sbt sbu scb scc scn scs sct scu snb snc snn sns snt snu ss- ssb ssc ssn sss sst ssu stb stc stn sts stt stu sub suc sun sus sut suu tbb tbc tbn tbs tbt tbu tcb tcc tcn tcs tct tcu tnb tnc tnn tns tnt tsb tsc tsn tss tst tsu ttb ttc ttn tts ttt ttu tub tuc tun tus tut tuu ubb ubc ubn ubs ubt ubu ucb ucc ucn ucs uct ucu un- unb unc unn uns unt unu usb usc usn uss ust usu utb utc utn uts utt utu uuc uun uus uut uuu