a-a aaa aad aaf aag aao ad- ada add adf adg ado af- afa afd aff afg afo ag- aga agd agf agg ago aoa aod aof aog aoo daa dad daf dag dao dda ddd ddf ddg ddo dfa dfd dff dfg dfo dga dgd dgf dgg doa dod dof dog doo faa fad faf fag fao fda fdd fdf fdg fdo ffa ffd fff ffg ffo fga fgd fgf fgg foa fof fog foo g-d gaa gad gaf gag gao gda gdd gdf gdo gfa gfd gff gfo gga ggd ggg ggo goa god gof gog goo oaa oad oaf oag oao oda odd odf odg odo of- ofa ofd off ofg ofo oga ogd ogf ogg ogo oo- ooa ood oof oog ooo