a-a a-b a-z aaa aab aag aah aaz ab- aba abb abg abh abz ag- aga agb agg agh agz aha ahb ahg ahh ahz az- aza azb azg azz baa bab bag bah baz bba bbb bbg bbh bga bgb bgg bgh bgz bha bhb bhg bhh bza bzh bzz gaa gab gag gah gaz gba gbg gbh gbz gga ggb ggg ggh ggz gha ghb ghg ghh ghz gza haa hab hag hah haz hba hbb hbg hbh hbz hga hgb hgg hgh hha hhb hhg hhh hhz z-g zaa zab zag zah zaz zbb zgb zgg zha zzz