a-a a-b aaa aab aad aan aao aar aas ab- aba abb abd abn abo abr abs ad- ada adb add adn ado adr ads an- ana anb and ann ano anr ans aoa aob aod aon aoo aor aos ar- ara arb ard arn aro arr ars as- asa asb asd asn aso asr ass baa bab bad ban bao bar bas bba bbb bbd bbn bbo bbr bbs bda bdb bdd bdo bdr bds bna bnb bnd bnn bno bnr bns boa bob bod bon boo bor bos bra brb brd brn bro brr brs bsa bsb bsd bsn bso bsr bss daa dab dad dan dao dar das dba dbb dbd dbn dbo dbr dbs dda ddb ddd ddn ddo ddr dds dna dnb dnd dnn dno dnr dns doa dob dod don doo dor dos dra drb drd drn dro drr drs dsa dsb dsd dsn dso dsr dss naa nab nad nan nao nar nas nba nbb nbd nbn nbo nbr nbs nda ndb ndd ndn ndo ndr nds nna nnb nnn nno nns no- noa nob nod non noo nor nos nra nrb nrd nrn nro nrr nrs nsa nsb nsd nsn nso nsr nss oaa oab oad oan oao oar oas ob- oba obb obd obn obo obr obs oda odb odd odn odo odr ods on- ona onb ond onn ono onr ons oo- ooa oob ood oon ooo oor oos or- ora orb ord orn oro orr ors os- osa osb osd osn oso osr oss ra- raa rab rad ran rao rar ras rba rbb rbd rbn rbo rbr rbs rda rdb rdd rdn rdo rdr rds rna rnb rnd rnn rno rnr rns roa rob rod ron roo ror ros rra rrb rrd rrn rrr rrs rsa rsb rsd rsn rso rsr rss saa sab sad san sao sar sas sba sbb sbd sbn sbo sbr sbs sda sdb sdd sdn sdo sdr sds sna snb snd snn sno snr sns soa sob sod son soo sor sos sr- sra srb srd srn sro srr srs ss- ssa ssb ssd ssn sso ssr sss