-er a-a a-b aaa aab aad aae aag aao aar aas ab- aba abb abd abe abg abo abr abs ad- ada adb add ade adg ado adr ads aea aeb aed aee aeg aeo aer aes ag- aga agb agd age agg ago agr ags aoa aob aod aoe aog aoo aor aos ar- ara arb ard are arg aro arr ars as- asa asb asd ase asg aso asr ass baa bab bad bae bag bao bar bas bba bbb bbd bbe bbg bbo bbr bbs bda bdb bdd bde bdg bdo bdr bds be- bea beb bed bee beg beo ber bes bga bgb bgd bge bgg bgo bgr bgs boa bob bod boe bog boo bor bos bra brb brd bre brg bro brr brs bsa bsb bsd bse bsg bso bsr bss daa dab dad dae dag dao dar das dba dbb dbd dbe dbg dbo dbr dbs dda ddb ddd dde ddg ddo ddr dds de- dea deb ded dee deg deo der des dga dgd dge dgg dgr dgs doa dob dod doe dog doo dor dos dra drb drd dre drg dro drr drs dsa dsb dsd dse dsg dso dsr dss eaa eab ead eae eag eao ear eas eba ebb ebd ebe ebg ebo ebr ebs ed- eda edb edd ede edg edo edr eds eea eeb eed eee eeg eeo eer ees ega egb egd ege egg ego egr egs eo- eoa eob eod eoe eog eoo eor eos era erb erd ere erg ero err ers es- esa esb esd ese esg eso esr ess g-d gaa gab gad gae gag gao gar gas gba gbd gbe gbg gbo gbr gbs gda gdb gdd gde gdo gdr gds ge- gea geb ged gee geg geo ger ges gga ggb ggd ggg ggo ggr ggs goa gob god goe gog goo gor gos gra grb grd gre grg gro grr grs gsa gsb gsd gse gsg gso gsr gss oaa oab oad oae oag oao oar oas ob- oba obb obd obe obg obo obr obs oda odb odd ode odg odo odr ods oea oeb oed oee oeg oeo oer oes oga ogd oge ogg ogo ogs oo- ooa oob ood oog ooo oor oos or- ora orb ord ore org oro orr ors os- osa osb osd ose osg oso osr oss ra- raa rab rad rae rag rao rar ras rba rbb rbd rbe rbg rbo rbr rbs rda rdb rdd rde rdg rdo rdr rds re- rea reb red ree reg reo rer res rga rgb rgd rge rgg rgo rgr rgs roa rob rod roe rog roo ror ros rra rrb rrd rrg rrr rrs rsa rsb rsd rse rsg rso rsr rss saa sab sad sae sag sao sar sas sba sbb sbd sbe sbg sbo sbr sbs sda sdb sdd sde sdg sdo sdr sds se- sea seb sed see seg seo ser ses sga sgb sgd sge sgg sgo sgr sgs soa sob sod soe sog soo sor sos sr- sra srb srd sre srg sro srr srs ss- ssa ssb ssd sse ssg sso ssr sss