a-a a-b a-t aaa aab aad aae aaf aao aas aat ab- aba abb abd abe abf abo abs abt ad- ada adb add ade adf ado ads adt aea aeb aed aee aef aeo aes aet af- afa afb afd afe aff afo afs aft aoa aob aod aoe aof aoo aos aot as- asa asb asd ase asf aso ass ast at- ata atb atd ate atf ato ats att baa bab bad bae baf bao bas bat bba bbb bbd bbe bbf bbo bbs bbt bda bdb bdd bde bdf bdo bds bdt be- bea beb bed bee bef beo bes bet bfa bfb bfd bfe bff bfo bfs bft boa bob bod boe bof boo bos bot bsa bsb bsd bse bsf bso bss bst bta btb btd bte btf bto bts btt daa dab dad dae daf dao das dat dba dbb dbd dbe dbf dbo dbs dbt dda ddb ddd dde ddf ddo dds ddt de- dea deb ded dee def deo des det dfa dfb dfd dfe dff dfo dfs dft doa dob dod doe dof doo dos dot dsa dsb dsd dse dsf dso dss dst dta dtb dtd dte dtf dto dts dtt eaa eab ead eae eaf eao eas eat eba ebb ebd ebe ebf ebo ebs ebt ed- eda edb edd ede edf edo eds edt eea eeb eed eee eef eeo ees eet ef- efa efb efd efe eff efo efs eft eo- eoa eob eod eoe eof eoo eos eot es- esa esb esd ese esf eso ess est eta etb etd ete etf eto ets ett faa fab fad fae faf fao fas fat fba fbb fbd fbe fbf fbo fbs fbt fda fdb fdd fde fdf fdo fds fdt fea feb fed fee fef feo fes fet ffa ffd ffe fff ffo ffs fft foa fob foe fof foo fos fot fsa fsb fsd fse fsf fso fss fst fta ftb ftd fte ftf fto fts ftt oaa oab oad oae oaf oao oas oat ob- oba obb obd obe obf obo obs obt oda odb odd ode odf odo ods odt oea oeb oed oee oef oeo oes oet of- ofa ofb ofd ofe off ofo ofs oft oo- ooa oob ood oof ooo oos oot os- osa osb osd ose osf oso oss ost ot- ota otb otd ote otf oto ots ott saa sab sad sae saf sao sas sat sba sbb sbd sbe sbf sbo sbs sbt sda sdb sdd sde sdf sdo sds sdt se- sea seb sed see sef seo ses set sfa sfb sfd sfe sff sfo sfs sft soa sob sod soe sof soo sos sot ss- ssa ssb ssd sse ssf sso sss sst sta stb std ste stf sto sts stt taa tab tad tae taf tao tas tat tba tbb tbd tbe tbf tbo tbs tbt tda tdb tdd tde tdf tdo tds tdt te- tea teb ted tee tef teo tes tet tfa tfb tfd tfe tff tfo tfs tft to- toa tob tod toe tof too tos tot tsa tsb tsd tse tsf tso tss tst tta ttb ttd tte ttf tto tts ttt