a-a a-b aaa aab aad aam aan aao ab- aba abb abd abm abn abo ad- ada adb add adm adn ado ama amb amd amm amn amo an- ana anb and anm ann ano aoa aob aod aom aon aoo baa bab bad bam ban bao bba bbb bbd bbm bbn bbo bda bdb bdd bdm bdo bma bmb bmd bmm bmn bmo bna bnb bnd bnn bno boa bob bod bom bon boo daa dab dad dam dan dao dba dbb dbd dbm dbn dbo dda ddb ddd ddm ddn ddo dma dmb dmd dmm dmn dmo dna dnb dnd dnm dnn dno doa dob dod dom don doo m-o maa mab mad mam man mao mba mbb mbd mbm mbo mda mdb mdd mdm mdn mdo mma mmb mmd mmm mmn mmo mna mnb mnm mnn mno moa mob mod mom mon moo naa nab nad nam nan nao nba nbb nbd nbm nbn nbo nda ndb ndd ndm ndn ndo nma nmb nmd nmm nmn nmo nna nnb nnm nnn nno no- noa nob nod nom non noo oaa oab oad oam oan oao ob- oba obb obd obm obn obo oda odb odd odm odn odo om- oma omb omd omm omn omo on- ona onb ond onn ono oo- ooa oob ood oom oon ooo