a-a a-b aaa aab aag aah aas ab- aba abb abg abh abs ag- aga agb agg agh ags aha ahb ahg ahh ahs as- asa asb asg ash ass baa bab bag bah bas bba bbb bbg bbh bbs bga bgb bgg bgh bgs bha bhb bhg bhh bhs bsa bsb bsg bsh bss gaa gab gag gah gas gba gbg gbh gbs gga ggb ggg ggh ggs gha ghb ghg ghh ghs gsa gsb gsg gss haa hab hag hah has hba hbb hbg hbh hbs hga hgb hgg hgh hgs hha hhb hhg hhh hhs hsa hsb hsg hsh hss saa sab sag sah sas sba sbb sbg sbh sbs sga sgb sgg sgh sgs sh- sha shb shg shh shs ss- ssa ssb ssg ssh sss