a-a a-b aaa aab aaf aam aan aao aau ab- aba abb abf abm abn abo abu af- afa afb aff afm afn afo afu ama amb amf amm amn amo amu an- ana anb anf anm ann ano anu aoa aob aof aom aon aoo aou au- aua aub auf aum aun auo b-u baa bab baf bam ban bao bau bba bbb bbf bbm bbn bbo bbu bfa bfb bff bfm bfn bfo bfu bma bmb bmf bmm bmn bmo bmu bna bnb bnf bnn bno bnu boa bob bof bom bon boo bou bua bub buf bum bun buo buu faa fab faf fam fan fao fau fba fbb fbf fbm fbn fbo fbu ffa fff ffm ffn ffo ffu fma fmb fmf fmm fmn fmo fmu fna fnb fnf fnm fnn fnu foa fob fof fom fon foo fou fua fub fuf fum fun fuo fuu m-f m-o maa mab maf mam man mao mau mba mbb mbf mbm mbo mbu mfa mfb mff mfm mfn mfo mfu mma mmb mmf mmm mmn mmo mmu mna mnb mnf mnm mnn mno mnu moa mob mof mom mon moo mou mua mub muf mum mun muu naa nab naf nam nan nao nau nba nbb nbf nbm nbn nbo nbu nfa nfb nff nfn nfo nfu nma nmb nmm nmn nmo nmu nna nnb nnf nnm nnn nno nnu no- noa nob nof nom non noo nou nua nub num nun nuo nuu oaa oab oaf oam oan oao oau ob- oba obb obf obm obn obo obu of- ofa ofb off ofm ofn ofo ofu om- oma omb omf omm omn omo omu on- ona onb onf onn ono onu oo- ooa oob oof oom oon ooo ou- oua ouf oum oun ouo ua- uaa uab uaf uam uan uao uau uba ubb ubf ubn ubo ubu ufa uff ufm ufn ufo ufu um- uma umb umf umm umn umo umu un- una unb unf unm unn uno unu uoa uob uom uon uoo uua uum uun uuu