a-a a-c a-t aaa aac aad aaf aao aat ac- aca acc acd acf aco act ad- ada adc add adf ado adt af- afa afc afd aff afo aft aoa aoc aod aof aoo aot at- ata atc atd atf ato att c-- caa cac cad caf cao cat cca ccc ccd ccf cco cct cda cdc cdd cdf cdo cdt cfa cfc cfd cff cfo cft co- coa coc cod cof coo cot cta ctc ctd ctf cto ctt daa dac dad daf dao dat dca dcc dcd dcf dco dct dda ddc ddd ddf ddo ddt dfa dfc dfd dff dfo dft doa doc dod dof doo dot dta dtc dtd dtf dto dtt faa fac fad faf fao fat fca fcc fcd fcf fco fct fda fdc fdd fdf fdo fdt ffa ffc ffd fff ffo fft foa foc fof foo fot fta ftc ftd ftf fto ftt oaa oac oad oaf oao oat oc- oca occ ocd ocf oco oct oda odc odd odf odo odt of- ofa ofc ofd off ofo oft oo- ooa ooc ood oof ooo oot ot- ota otc otd otf oto ott taa tac tad taf tao tat tca tcc tcd tcf tco tct tda tdc tdd tdf tdo tdt tfa tfc tfd tff tfo tft to- toa toc tod tof too tot tta ttc ttd ttf tto ttt