a-a a-b a-t aaa aab aad aan aao aas aat ab- aba abb abd abn abo abs abt ad- ada adb add adn ado ads adt an- ana anb and ann ano ans ant aoa aob aod aon aoo aos aot as- asa asb asd asn aso ass ast at- ata atb atd atn ato ats att baa bab bad ban bao bas bat bba bbb bbd bbn bbo bbs bbt bda bdb bdd bdo bds bdt bna bnb bnd bnn bno bns bnt boa bob bod bon boo bos bot bsa bsb bsd bsn bso bss bst bta btb btd btn bto bts btt daa dab dad dan dao das dat dba dbb dbd dbn dbo dbs dbt dda ddb ddd ddn ddo dds ddt dna dnb dnd dnn dno dns dnt doa dob dod don doo dos dot dsa dsb dsd dsn dso dss dst dta dtb dtd dtn dto dts dtt naa nab nad nan nao nas nat nba nbb nbd nbn nbo nbs nbt nda ndb ndd ndn ndo nds ndt nna nnb nnn nno nns nnt no- noa nob nod non noo nos not nsa nsb nsd nsn nso nss nst nta ntb ntd ntn nto nts ntt oaa oab oad oan oao oas oat ob- oba obb obd obn obo obs obt oda odb odd odn odo ods odt on- ona onb ond onn ono ons ont oo- ooa oob ood oon ooo oos oot os- osa osb osd osn oso oss ost ot- ota otb otd otn oto ots ott saa sab sad san sao sas sat sba sbb sbd sbn sbo sbs sbt sda sdb sdd sdn sdo sds sdt sna snb snd snn sno sns snt soa sob sod son soo sos sot ss- ssa ssb ssd ssn sso sss sst sta stb std stn sto sts stt taa tab tad tan tao tas tat tba tbb tbd tbn tbo tbs tbt tda tdb tdd tdn tdo tds tdt tna tnb tnd tnn tno tns tnt to- toa tob tod ton too tos tot tsa tsb tsd tsn tso tss tst tta ttb ttd ttn tto tts ttt