-ey a-a a-b a-c aaa aab aac aad aae aay ab- aba abb abc abd abe aby ac- aca acb acc acd ace acy ad- ada adb adc add ade ady aea aeb aec aed aee aey ay- aya ayc ayd aye baa bab bac bad bae bay bba bbb bbc bbd bbe bby bca bcb bcc bcd bce bcy bda bdb bdc bdd bde bdy be- bea beb bec bed bee bey by- bya byc byd bye c-- caa cab cac cad cae cay cba cbb cbc cbd cbe cby cca ccb ccc ccd cce cda cdb cdc cdd cde cdy ce- cea ceb cec ced cee cey cya cyb cyc cyd cye daa dab dac dad dae day dba dbb dbc dbd dbe dby dca dcb dcc dcd dce dda ddb ddc ddd dde ddy de- dea deb dec ded dee dey dy- dya dyb dyc dyd dye dyy eaa eab eac ead eae eba ebb ebc ebd ebe eby ec- eca ecb ecc ecd ece ed- eda edb edc edd ede edy eea eeb eec eed eee eey eya eyc eyd eye yaa yab yac yad yae yay ybc ybe yby yca ycc ycd yce ycy yda yde ydy yea yeb yec yed yee yey yyb yyc yye yyy