a-a a-t aaa aad aaf aao aas aat ad- ada add adf ado ads adt af- afa afd aff afo afs aft aoa aod aof aoo aos aot as- asa asd asf aso ass ast at- ata atd atf ato ats att daa dad daf dao das dat dda ddd ddf ddo dds ddt dfa dfd dff dfo dfs dft doa dod dof doo dos dot dsa dsd dsf dso dss dst dta dtd dtf dto dts dtt faa fad faf fao fas fat fda fdd fdf fdo fds fdt ffa ffd fff ffo ffs fft foa fof foo fos fot fsa fsd fsf fso fss fst fta ftd ftf fto fts ftt oaa oad oaf oao oas oat oda odd odf odo ods odt of- ofa ofd off ofo ofs oft oo- ooa ood oof ooo oos oot os- osa osd osf oso oss ost ot- ota otd otf oto ots ott saa sad saf sao sas sat sda sdd sdf sdo sds sdt sfa sfd sff sfo sfs sft soa sod sof soo sos sot ss- ssa ssd ssf sso sss sst sta std stf sto sts stt taa tad taf tao tas tat tda tdd tdf tdo tds tdt tfa tfd tff tfo tfs tft to- toa tod tof too tos tot tsa tsd tsf tso tss tst tta ttd ttf tto tts ttt