a-a a-b aaa aab aad aam aan aar aax ab- aba abb abd abm abn abr abx ad- ada adb add adm adn adr adx ama amb amd amm amn amr amx an- ana anb and anm ann anr anx ar- ara arb ard arm arn arr arx ax- axa axm axn axr axx baa bab bad bam ban bar bax bba bbb bbd bbm bbn bbr bbx bda bdb bdd bdm bdr bdx bma bmb bmd bmm bmn bmr bmx bna bnb bnd bnn bnr bnx bra brb brd brm brn brr brx bxb bxd bxm bxn bxx daa dab dad dam dan dar dax dba dbb dbd dbm dbn dbr dbx dda ddb ddd ddm ddn ddr ddx dma dmb dmd dmm dmn dmr dmx dna dnb dnd dnm dnn dnr dra drb drd drm drn drr drx dxd dxn dxr dxx m-r maa mab mad mam man mar max mba mbb mbd mbm mbr mbx mda mdb mdd mdm mdn mdr mdx mma mmb mmd mmm mmn mmr mmx mna mnb mnm mnn mnr mra mrb mrd mrm mrn mrr mrx mxa mxd mxn mxr naa nab nad nam nan nar nax nba nbb nbd nbm nbn nbr nbx nda ndb ndd ndm ndn ndr nma nmb nmd nmm nmn nmr nna nnb nnm nnn nra nrb nrd nrm nrn nrr nrx nxd ra- raa rab rad ram ran rar rax rba rbb rbd rbm rbn rbr rbx rda rdb rdd rdm rdn rdr rdx rma rmb rmd rmm rmn rmr rmx rna rnb rnd rnm rnn rnr rra rrb rrd rrm rrn rrr rxr xaa xad xam xan xar xbr xbx xda xdb xdm xdr xma xmd xmm xmr xmx xna xrd xrx xxx