b-u bbb bbc bbd bbf bbk bbu bby bcb bcc bcd bcf bck bcu bcy bdb bdc bdd bdf bdk bdu bdy bfb bfc bfd bff bfu bfy bkb bkc bkf bkk bub buc bud buf buk buu buy by- byc byd byf byk byu c-- cbb cbc cbd cbf cbk cbu cby ccb ccc ccd ccf cck ccu cdb cdc cdd cdf cdk cdu cdy cfb cfc cfd cff cfk cfu ckb ckc ckd cky cub cuc cud cuf cuk cuu cuy cyb cyc cyd cyf cyk dbb dbc dbd dbf dbk dbu dby dcb dcc dcd dcf dck dcu ddb ddc ddd ddf ddk ddu ddy dfb dfc dfd dff dfk dfu dkb dkc dkk dku dub duc dud duf duk duy dy- dyb dyc dyd dyk dyu dyy fbb fbc fbd fbf fbk fbu fcb fcc fcd fcf fck fcu fcy fdb fdc fdd fdf fdk fdu ffc ffd fff ffk ffu ffy fkb fkc fkf fkk fub fud fuf fuk fuu fy- fyb fyc fyk kbb kbc kbd kbf kbk kbu kcb kcc kcd kck kcu kdb kdc kdf kdk kdu kdy kfc kfd kff kfu kkb kkc kkk kku kky kub kuc kud kuk kuu kuy kyc kyd kyu ubb ubc ubf ubk ubu uby ucb ucc ucd ucf uck ucu udb udc udd udf udk udu ufc ufd uff ufu ukb ukc ukf ukk uku uuc uuu uyc uyu ybc ybf yby ycc ycd ycf ycu ycy ydy yfc yfd yff yfu ykk yud yuk yuu yuy yyb yyc yyf yyu yyy