a-a a-c a-t aaa aac aaf aat aay ac- aca acc acf act acy af- afa afc aff aft afy at- ata atc atf att ay- aya ayc ayf ayt c-- caa cac caf cat cay cca ccc ccf cct cfa cfc cff cft cta ctc ctf ctt cty cya cyc cyf cyt faa fac faf fat fay fca fcc fcf fct fcy ffa ffc fff fft ffy fta ftc ftf ftt fty fy- fya fyc taa tac taf tat tay tca tcc tcf tct tfa tfc tff tft tta ttc ttf ttt tty tya tyc tyf tyt yaa yac yaf yat yay yca ycc ycf ycy yfa yfc yff yft yta ytc ytf ytt yyc yyf yyt yyy