a-a a-b a-c a-z aaa aab aac aak aau aay aaz ab- aba abb abc abk abu aby abz ac- aca acb acc ack acu acy acz aka akb akc akk aku au- aua aub auc auk auz ay- aya ayc ayk ayu ayz az- aza azb azu azy azz b-u baa bab bac bak bau bay baz bba bbb bbc bbk bbu bby bca bcb bcc bck bcu bcy bcz bka bkb bkc bkk bua bub buc buk buu buy buz by- bya byc byk byu byz bza bzu bzz c-- caa cab cac cak cau cay caz cba cbb cbc cbk cbu cby cbz cca ccb ccc cck ccu ccz cka ckb ckc cky cua cub cuc cuk cuu cuy cuz cya cyb cyc cyk cz- czc czk k-z ka- kaa kab kac kak kau kay kaz kba kbb kbc kbk kbu kbz kca kcb kcc kck kcu kkb kkc kkk kku kky kub kuc kuk kuu kuy kya kyc kyu kyz kzy ua- uaa uab uac uak uau uay uaz uba ubb ubc ubk ubu uby uca ucb ucc uck ucu uka ukb ukc ukk uku ukz uua uuc uuu uyc uyu uza uzb uzu yaa yab yac yak yau yay yaz ybc yby ybz yca ycc ycu ycy yka ykk yua yuk yuu yuy yyb yyc yyu yyy yyz yzb yzu yzy zaa zab zac zak zay zaz zbb zbc zby zka zub zuc zuk zuz zzy zzz