a-a a-b a-c aaa aab aac aag aah aar ab- aba abb abc abg abh abr ac- aca acb acc acg ach acr ag- aga agb agc agg agh agr aha ahb ahc ahg ahh ahr ar- ara arb arc arg arh arr baa bab bac bag bah bar bba bbb bbc bbg bbh bbr bca bcb bcc bcg bch bcr bga bgb bgc bgg bgh bgr bha bhb bhc bhg bhh bhr bra brb brg brh brr c-- caa cab cac cag cah car cba cbb cbc cbg cbh cbr cca ccb ccc ccg cch ccr cga cgb cgc cgg cgh cgr ch- cha chb chc chg chh chr cra crb crc crg crh crr gaa gab gac gag gah gar gba gbc gbg gbh gbr gca gcb gcc gcg gch gcr gga ggb ggc ggg ggh ggr gha ghb ghc ghg ghh ghr gra grb grc grg grh grr haa hab hac hag hah har hba hbb hbc hbg hbh hbr hca hcb hcc hcg hch hcr hga hgb hgc hgg hgh hgr hha hhb hhc hhg hhh hhr hr- hra hrb hrc hrg hrh hrr ra- raa rab rac rag rah rar rba rbb rbc rbg rbh rbr rca rcb rcc rcg rch rcr rga rgb rgc rgg rgh rgr rh- rha rhb rhc rhg rhh rhr rra rrb rrc rrg rrh rrr