a-a aaa aaf aag aak aao aar aas af- afa aff afg afk afo afr afs ag- aga agf agg agk ago agr ags aka akg akk ako akr aks aoa aof aog aok aoo aor aos ar- ara arf arg ark aro arr ars as- asa asf asg ask aso asr ass faa faf fag fak fao far fas ffa fff ffg ffk ffo ffr ffs fga fgf fgg fgr fgs fka fkf fkg fkk foa fof fog fok foo for fos fra frf frg frk fro frr frs fsa fsf fsg fsk fso fsr fss gaa gaf gag gak gao gar gas gfa gff gfk gfo gfr gfs gga ggg ggo ggr ggs gka gko gks goa gof gog gok goo gor gos gra grf grg grk gro grr grs gsa gsf gsg gsk gso gsr gss ka- kaa kaf kag kak kao kar kas kfa kff kfg kfo kfs kga kgf kgo kgs kkk kkr kks koa kof kog kok koo kor kos kra krf krg krk kro krr krs ksa ksf ksg ksk kso ksr kss oaa oaf oag oak oao oar oas of- ofa off ofg ofo ofr ofs oga ogf ogg ogo ogs oka okg okk oko okr oks oo- ooa oof oog ook ooo oor oos or- ora orf org ork oro orr ors os- osa osf osg osk oso osr oss ra- raa raf rag rak rao rar ras rfa rff rfg rfk rfo rfr rfs rga rgf rgg rgk rgo rgr rgs rkf rkg rkk rko rks roa rof rog rok roo ror ros rra rrf rrg rrk rrr rrs rsa rsf rsg rsk rso rsr rss saa saf sag sak sao sar sas sfa sff sfg sfk sfo sfr sfs sga sgf sgg sgk sgo sgr sgs sk- ska skf skg skk sko skr sks soa sof sog sok soo sor sos sr- sra srf srg srk sro srr srs ss- ssa ssf ssg ssk sso ssr sss