b-u bbb bbc bbk bbm bbr bbs bbt bbu bcb bcc bck bcm bcr bcs bct bcu bkb bkc bkk bkm bkr bks bkt bmb bmc bmk bmm bmr bms bmt bmu brb brk brm brr brs brt bru bsb bsc bsk bsm bsr bss bst bsu btb btc btk btm btr bts btt btu bub buc buk bum bur bus but buu c-- cbb cbc cbk cbm cbr cbs cbt cbu ccb ccc cck ccm ccr ccs cct ccu ckb ckc ckm cks ckt cmb cmc cmk cmm cmr cms cmt cmu crb crc crk crm crr crs crt cru csb csc csk csm csr css cst csu ctb ctc ctk ctm ctr cts ctt ctu cub cuc cuk cum cur cus cut cuu k-t kbb kbc kbk kbm kbr kbs kbu kcb kcc kck kcm kcr kcs kct kcu kkb kkc kkk kkm kkr kks kkt kku kmb kmc kmk kmm kms kmt kmu krc krk krr krs krt kru ksb ksc ksk ksm ksr kss kst ksu ktb ktc ktk ktm ktr kts ktt ktu kub kuc kuk kum kur kus kut kuu m-r mbb mbc mbk mbm mbr mbs mbt mbu mc- mcb mcc mck mcm mcr mcs mct mcu mkb mkc mkk mkm mkr mks mkt mku mmb mmc mmk mmm mmr mms mmt mmu mrb mrc mrk mrm mrr mrs mrt mru msb msc msk msm msr mss mst msu mtb mtc mtk mtm mtr mts mtt mtu mub muc muk mum mur mus mut muu rbb rbc rbk rbm rbr rbs rbt rbu rcb rcc rcm rcr rcs rct rcu rkb rkc rkk rkm rks rkt rku rmb rmc rmm rmr rms rmt rrb rrc rrk rrm rrr rrs rrt rru rsb rsc rsk rsm rsr rss rst rsu rtb rtc rtk rtm rtr rts rtt rtu rub ruc ruk rum rur rus rut ruu sbb sbc sbk sbm sbr sbs sbt sbu scb scc sck scm scr scs sct scu sk- skb skc skk skm skr sks skt sku smb smc smk smm smr sms smt smu sr- srb src srk srm srr srs srt ss- ssb ssc ssk ssm ssr sss sst ssu stb stc stk stm str sts stt stu sub suc suk sum sur sus sut suu tbb tbc tbk tbm tbr tbs tbt tbu tcb tcc tck tcm tcr tcs tct tcu tkb tkc tkk tkm tkr tks tkt tmb tmc tmk tmm tmr tms tmt tmu trb trc trk trm trr trs trt tru tsb tsc tsk tsm tsr tss tst tsu ttb ttc ttk ttm ttr tts ttt ttu tub tuc tuk tum tur tus tut tuu ubb ubc ubk ubr ubs ubt ubu ucb ucc uck ucm ucr ucs uct ucu ukb ukc ukk ukr uku um- umb umc umm umr ums umt umu ur- urb urc urk urm urr urs urt uru usb usc usk usm usr uss ust usu utb utc utk utm utr uts utt utu uuc uum uur uus uut uuu