a-a a-b a-c a-t aaa aab aac aad aae aao aas aat ab- aba abb abc abd abe abo abs abt ac- aca acb acc acd ace aco acs act ad- ada adb adc add ade ado ads adt aea aeb aec aed aee aeo aes aet aoa aob aoc aod aoe aoo aos aot as- asa asb asc asd ase aso ass ast at- ata atb atc atd ate ato ats att baa bab bac bad bae bao bas bat bba bbb bbc bbd bbe bbo bbs bbt bca bcb bcc bcd bce bco bcs bct bda bdb bdc bdd bde bdo bds bdt be- bea beb bec bed bee beo bes bet boa bob boc bod boe boo bos bot bsa bsb bsc bsd bse bso bss bst bta btb btc btd bte bto bts btt c-- caa cab cac cad cae cao cas cat cba cbb cbc cbd cbe cbo cbs cbt cca ccb ccc ccd cce cco ccs cct cda cdb cdc cdd cde cdo cds cdt ce- cea ceb cec ced cee ceo ces cet co- coa cob coc cod coe coo cos cot csa csb csc csd cse cso css cst cta ctb ctc ctd cte cto cts ctt daa dab dac dad dae dao das dat dba dbb dbc dbd dbe dbo dbs dbt dca dcb dcc dcd dce dco dcs dct dda ddb ddc ddd dde ddo dds ddt de- dea deb dec ded dee deo des det doa dob doc dod doe doo dos dot dsa dsb dsc dsd dse dso dss dst dta dtb dtc dtd dte dto dts dtt eaa eab eac ead eae eao eas eat eba ebb ebc ebd ebe ebo ebs ebt ec- eca ecb ecc ecd ece eco ecs ect ed- eda edb edc edd ede edo eds edt eea eeb eec eed eee eeo ees eet eo- eoa eob eoc eod eoe eoo eos eot es- esa esb esc esd ese eso ess est eta etb etc etd ete eto ets ett oaa oab oac oad oae oao oas oat ob- oba obb obc obd obe obo obs obt oc- oca ocb occ ocd oco ocs oct oda odb odc odd ode odo ods odt oea oeb oec oed oee oeo oes oet oo- ooa oob ooc ood ooo oos oot os- osa osb osc osd ose oso oss ost ot- ota otb otc otd ote oto ots ott saa sab sac sad sae sao sas sat sba sbb sbc sbd sbe sbo sbs sbt sca scb scc scd sce sco scs sct sda sdb sdc sdd sde sdo sds sdt se- sea seb sec sed see seo ses set soa sob soc sod soe soo sos sot ss- ssa ssb ssc ssd sse sso sss sst sta stb stc std ste sto sts stt taa tab tac tad tae tao tas tat tba tbb tbc tbd tbe tbo tbs tbt tca tcb tcc tcd tce tco tcs tct tda tdb tdc tdd tde tdo tds tdt te- tea teb tec ted tee teo tes tet to- toa tob toc tod toe too tos tot tsa tsb tsc tsd tse tso tss tst tta ttb ttc ttd tte tto tts ttt