a-a a-c a-t aaa aac aad aaf aar aas aat ac- aca acc acd acf acr acs act ad- ada adc add adf adr ads adt af- afa afc afd aff afr afs aft ar- ara arc ard arf arr ars art as- asa asc asd asf asr ass ast at- ata atc atd atf atr ats att c-- caa cac cad caf car cas cat cca ccc ccd ccf ccr ccs cct cda cdc cdd cdf cdr cds cdt cfa cfc cfd cff cfr cfs cft cra crc crd crf crr crs crt csa csc csd csf csr css cst cta ctc ctd ctf ctr cts ctt daa dac dad daf dar das dat dca dcc dcd dcf dcr dcs dct dda ddc ddd ddf ddr dds ddt dfa dfc dfd dff dfr dfs dft dra drc drd drr drs drt dsa dsc dsd dsf dsr dss dst dta dtc dtd dtf dtr dts dtt faa fac fad faf far fas fat fca fcc fcd fcf fcr fcs fct fda fdc fdd fdf fdr fds fdt ffa ffc ffd fff ffr ffs fft fra frc frd frf frr frs frt fsa fsc fsd fsf fsr fss fst fta ftc ftd ftf ftr fts ftt ra- raa rac rad raf rar ras rat rca rcc rcd rcf rcr rcs rct rda rdc rdd rdf rdr rds rdt rfa rfc rfd rff rfr rfs rft rra rrc rrd rrf rrr rrs rrt rsa rsc rsd rsf rsr rss rst rta rtc rtd rtf rtr rts rtt saa sac sad saf sar sas sat sca scc scd scf scr scs sct sda sdc sdd sdf sdr sds sdt sfa sfc sfd sff sfr sfs sft sr- sra src srd srf srr srs srt ss- ssa ssc ssd ssf ssr sss sst sta stc std stf str sts stt taa tac tad taf tar tas tat tca tcc tcd tcf tcr tcs tct tda tdc tdd tdf tdr tds tdt tfa tfc tfd tff tfr tfs tft tra trc trd trf trr trs trt tsa tsc tsd tsf tsr tss tst tta ttc ttd ttf ttr tts ttt