a-a a-c a-t aaa aac aad aaf aao aas aat ac- aca acc acd acf aco acs act ad- ada adc add adf ado ads adt af- afa afc afd aff afo afs aft aoa aoc aod aof aoo aos aot as- asa asc asd asf aso ass ast at- ata atc atd atf ato ats att c-- caa cac cad caf cao cas cat cca ccc ccd ccf cco ccs cct cda cdc cdd cdf cdo cds cdt cfa cfc cfd cff cfo cfs cft co- coa coc cod cof coo cos cot csa csc csd csf cso css cst cta ctc ctd ctf cto cts ctt daa dac dad daf dao das dat dca dcc dcd dcf dco dcs dct dda ddc ddd ddf ddo dds ddt dfa dfc dfd dff dfo dfs dft doa doc dod dof doo dos dot dsa dsc dsd dsf dso dss dst dta dtc dtd dtf dto dts dtt faa fac fad faf fao fas fat fca fcc fcd fcf fco fcs fct fda fdc fdd fdf fdo fds fdt ffa ffc ffd fff ffo ffs fft foa foc fof foo fos fot fsa fsc fsd fsf fso fss fst fta ftc ftd ftf fto fts ftt oaa oac oad oaf oao oas oat oc- oca occ ocd ocf oco ocs oct oda odc odd odf odo ods odt of- ofa ofc ofd off ofo ofs oft oo- ooa ooc ood oof ooo oos oot os- osa osc osd osf oso oss ost ot- ota otc otd otf oto ots ott saa sac sad saf sao sas sat sca scc scd scf sco scs sct sda sdc sdd sdf sdo sds sdt sfa sfc sfd sff sfo sfs sft soa soc sod sof soo sos sot ss- ssa ssc ssd ssf sso sss sst sta stc std stf sto sts stt taa tac tad taf tao tas tat tca tcc tcd tcf tco tcs tct tda tdc tdd tdf tdo tds tdt tfa tfc tfd tff tfo tfs tft to- toa toc tod tof too tos tot tsa tsc tsd tsf tso tss tst tta ttc ttd ttf tto tts ttt