a-a a-b a-z aaa aab aad aan aar aaz ab- aba abb abd abn abr abz ad- ada adb add adn adr adz an- ana anb and ann anr anz ar- ara arb ard arn arr arz az- aza azb azd azn azz baa bab bad ban bar baz bba bbb bbd bbn bbr bda bdb bdd bdr bdz bna bnb bnd bnn bnr bnz bra brb brd brn brr brz bza bzd bzn bzr bzz daa dab dad dan dar daz dba dbb dbd dbn dbr dbz dda ddb ddd ddn ddr ddz dna dnb dnd dnn dnr dnz dra drb drd drn drr drz dza dzb dzd dzr naa nab nad nan nar naz nba nbb nbd nbn nbr nda ndb ndd ndn ndr nna nnb nnn nnz nra nrb nrd nrn nrr nrz nzb nzd nzz ra- raa rab rad ran rar raz rba rbb rbd rbn rbr rda rdb rdd rdn rdr rna rnb rnd rnn rnr rnz rra rrb rrd rrn rrr rza rzb zaa zab zad zan zar zaz zbb zbr znd znn zzr zzz