-er a-a a-b a-t aaa aab aad aae aaf aar aas aat ab- aba abb abd abe abf abr abs abt ad- ada adb add ade adf adr ads adt aea aeb aed aee aef aer aes aet af- afa afb afd afe aff afr afs aft ar- ara arb ard are arf arr ars art as- asa asb asd ase asf asr ass ast at- ata atb atd ate atf atr ats att baa bab bad bae baf bar bas bat bba bbb bbd bbe bbf bbr bbs bbt bda bdb bdd bde bdf bdr bds bdt be- bea beb bed bee bef ber bes bet bfa bfb bfd bfe bff bfr bfs bft bra brb brd bre brf brr brs brt bsa bsb bsd bse bsf bsr bss bst bta btb btd bte btf btr bts btt daa dab dad dae daf dar das dat dba dbb dbd dbe dbf dbr dbs dbt dda ddb ddd dde ddf ddr dds ddt de- dea deb ded dee def der des det dfa dfb dfd dfe dff dfr dfs dft dra drb drd dre drr drs drt dsa dsb dsd dse dsf dsr dss dst dta dtb dtd dte dtf dtr dts dtt eaa eab ead eae eaf ear eas eat eba ebb ebd ebe ebf ebr ebs ebt ed- eda edb edd ede edf edr eds edt eea eeb eed eee eef eer ees eet ef- efa efb efd efe eff efr efs eft era erb erd ere erf err ers ert es- esa esb esd ese esf esr ess est eta etb etd ete etf etr ets ett faa fab fad fae faf far fas fat fba fbb fbd fbe fbf fbr fbs fbt fda fdb fdd fde fdf fdr fds fdt fea feb fed fee fef fer fes fet ffa ffd ffe fff ffr ffs fft fra frb frd fre frf frr frs frt fsa fsb fsd fse fsf fsr fss fst fta ftb ftd fte ftf ftr fts ftt ra- raa rab rad rae raf rar ras rat rba rbb rbd rbe rbf rbr rbs rbt rda rdb rdd rde rdf rdr rds rdt re- rea reb red ree ref rer res ret rfa rfb rfd rfe rff rfr rfs rft rra rrb rrd rrf rrr rrs rrt rsa rsb rsd rse rsf rsr rss rst rta rtb rtd rte rtf rtr rts rtt saa sab sad sae saf sar sas sat sba sbb sbd sbe sbf sbr sbs sbt sda sdb sdd sde sdf sdr sds sdt se- sea seb sed see sef ser ses set sfa sfb sfd sfe sff sfr sfs sft sr- sra srb srd sre srf srr srs srt ss- ssa ssb ssd sse ssf ssr sss sst sta stb std ste stf str sts stt taa tab tad tae taf tar tas tat tba tbb tbd tbe tbf tbr tbs tbt tda tdb tdd tde tdf tdr tds tdt te- tea teb ted tee tef ter tes tet tfa tfb tfd tfe tff tfr tfs tft tra trb trd tre trf trr trs trt tsa tsb tsd tse tsf tsr tss tst tta ttb ttd tte ttf ttr tts ttt