b-u bbb bbc bbf bbk bbm bbu bcb bcc bcf bck bcm bcu bfb bfc bff bfm bfu bkb bkc bkf bkk bkm bmb bmc bmf bmk bmm bmu bub buc buf buk bum buu c-- cbb cbc cbf cbk cbm cbu ccb ccc ccf cck ccm ccu cfb cfc cff cfk cfm cfu ckb ckc ckm cmb cmc cmf cmk cmm cmu cub cuc cuf cuk cum cuu fbb fbc fbf fbk fbm fbu fcb fcc fcf fck fcm fcu ffc fff ffk ffm ffu fkb fkc fkf fkk fkm fmb fmc fmf fmm fmu fub fuf fuk fum fuu kbb kbc kbf kbk kbm kbu kcb kcc kck kcm kcu kfc kff kfm kfu kkb kkc kkk kkm kku kmb kmc kmf kmk kmm kmu kub kuc kuk kum kuu m-f mbb mbc mbf mbk mbm mbu mc- mcb mcc mcf mck mcm mcu mfb mfc mff mfm mfu mkb mkc mkk mkm mku mmb mmc mmf mmk mmm mmu mub muc muf muk mum muu ubb ubc ubf ubk ubu ucb ucc ucf uck ucm ucu ufc uff ufm ufu ukb ukc ukf ukk uku um- umb umc umf umm umu uuc uum uuu