b-u bbb bbd bbf bbn bbs bbu bdb bdd bdf bds bdu bfb bfd bff bfn bfs bfu bnb bnd bnf bnn bns bnu bsb bsd bsf bsn bss bsu bub bud buf bun bus buu dbb dbd dbf dbn dbs dbu ddb ddd ddf ddn dds ddu dfb dfd dff dfn dfs dfu dnb dnd dnf dnn dns dsb dsd dsf dsn dss dsu dub dud duf dun dus fbb fbd fbf fbn fbs fbu fdb fdd fdf fdn fds fdu ffd fff ffn ffs ffu fnb fnd fnf fnn fns fnu fsb fsd fsf fsn fss fsu fub fud fuf fun fus fuu nbb nbd nbf nbn nbs nbu ndb ndd ndf ndn nds ndu nfb nfd nff nfn nfs nfu nnb nnf nnn nns nnu nsb nsd nsf nsn nss nsu nub nud nun nus nuu sbb sbd sbf sbn sbs sbu sdb sdd sdf sdn sds sdu sfb sfd sff sfn sfs sfu snb snd snf snn sns snu ss- ssb ssd ssf ssn sss ssu sub sud suf sun sus suu ubb ubf ubn ubs ubu udb udd udf udn uds udu ufd uff ufn ufs ufu un- unb und unf unn uns unu usb usd usf usn uss usu uun uus uuu