b-u bbb bbc bbd bbf bbk bbm bbs bbu bcb bcc bcd bcf bck bcm bcs bcu bdb bdc bdd bdf bdk bdm bds bdu bfb bfc bfd bff bfm bfs bfu bkb bkc bkf bkk bkm bks bmb bmc bmd bmf bmk bmm bms bmu bsb bsc bsd bsf bsk bsm bss bsu bub buc bud buf buk bum bus buu c-- cbb cbc cbd cbf cbk cbm cbs cbu ccb ccc ccd ccf cck ccm ccs ccu cdb cdc cdd cdf cdk cdm cds cdu cfb cfc cfd cff cfk cfm cfs cfu ckb ckc ckd ckm cks cmb cmc cmd cmf cmk cmm cms cmu csb csc csd csf csk csm css csu cub cuc cud cuf cuk cum cus cuu dbb dbc dbd dbf dbk dbm dbs dbu dcb dcc dcd dcf dck dcm dcs dcu ddb ddc ddd ddf ddk ddm dds ddu dfb dfc dfd dff dfk dfm dfs dfu dkb dkc dkk dkm dks dku dmb dmc dmd dmf dmk dmm dms dmu dsb dsc dsd dsf dsk dsm dss dsu dub duc dud duf duk dum dus fbb fbc fbd fbf fbk fbm fbs fbu fcb fcc fcd fcf fck fcm fcs fcu fdb fdc fdd fdf fdk fdm fds fdu ffc ffd fff ffk ffm ffs ffu fkb fkc fkf fkk fkm fmb fmc fmd fmf fmm fms fmu fsb fsc fsd fsf fsk fsm fss fsu fub fud fuf fuk fum fus fuu kbb kbc kbd kbf kbk kbm kbs kbu kcb kcc kcd kck kcm kcs kcu kdb kdc kdf kdk kdm kds kdu kfc kfd kff kfm kfs kfu kkb kkc kkk kkm kks kku kmb kmc kmd kmf kmk kmm kms kmu ksb ksc ksd ksf ksk ksm kss ksu kub kuc kud kuk kum kus kuu m-f mbb mbc mbd mbf mbk mbm mbs mbu mc- mcb mcc mcd mcf mck mcm mcs mcu mdb mdc mdd mdf mdk mdm mds mdu mfb mfc mfd mff mfm mfs mfu mkb mkc mkd mkk mkm mks mku mmb mmc mmd mmf mmk mmm mms mmu msb msc msd msf msk msm mss msu mub muc mud muf muk mum mus muu sbb sbc sbd sbf sbk sbm sbs sbu scb scc scd scf sck scm scs scu sdb sdc sdd sdf sdk sdm sds sdu sfb sfc sfd sff sfk sfm sfs sfu sk- skb skc skd skf skk skm sks sku smb smc smd smf smk smm sms smu ss- ssb ssc ssd ssf ssk ssm sss ssu sub suc sud suf suk sum sus suu ubb ubc ubf ubk ubs ubu ucb ucc ucd ucf uck ucm ucs ucu udb udc udd udf udk udm uds udu ufc ufd uff ufm ufs ufu ukb ukc ukf ukk uku um- umb umc umd umf umm ums umu usb usc usd usf usk usm uss usu uuc uum uus uuu