a-a a-b a-c a-z aaa aab aac aae aak aan aau aaz ab- aba abb abc abe abk abn abu abz ac- aca acb acc ace ack acn acu acz aea aeb aec aee aek aen aeu aez aka akb akc ake akk akn aku an- ana anb anc ane ank ann anu anz au- aua aub auc aue auk aun auz az- aza azb aze azn azu azz b-u baa bab bac bae bak ban bau baz bba bbb bbc bbe bbk bbn bbu bca bcb bcc bce bck bcn bcu bcz be- bea beb bec bee bek ben beu bez bka bkb bkc bke bkk bkn bna bnb bnc bne bnk bnn bnu bnz bua bub buc bue buk bun buu buz bza bze bzn bzu bzz c-- caa cab cac cae cak can cau caz cba cbb cbc cbe cbk cbn cbu cbz cca ccb ccc cce cck ccn ccu ccz ce- cea ceb cec cee cek cen ceu cez cka ckb ckc cn- cna cnb cnc cne cnn cnu cua cub cuc cue cuk cun cuu cuz cz- czc cze czk eaa eab eac eae eak ean eau eaz eba ebb ebc ebe ebk ebn ebu ec- eca ecb ecc ece eck ecn ecu eea eeb eec eee eek een eka ekb ekc eke eku en- ena enb enc ene enk enn enu enz eu- eua eub euc eue eun eze ezz k-z ka- kaa kab kac kae kak kan kau kaz kba kbb kbc kbe kbk kbn kbu kbz kca kcb kcc kce kck kcn kcu ke- kea keb kec kee kek ken kez kkb kkc kke kkk kkn kku kn- kna knc kne knk knn knu kub kuc kue kuk kun kuu naa nab nac nae nak nan nau naz nba nbb nbc nbe nbk nbn nbu nca ncb ncc nce nck ncn ncu ne- nea neb nec nee nek nen neu nez nka nkc nke nkk nkn nku nna nnb nnc nne nnk nnn nnu nnz nua nub nuc nue nuk nun nuu nzb nze nzz ua- uaa uab uac uae uak uan uau uaz uba ubb ubc ube ubk ubn ubu uca ucb ucc uce uck ucn ucu uea ueb uec uee uen uka ukb ukc uke ukk ukn uku ukz un- una unb unc une unk unn unu uua uuc uue uun uuu uza uzb uzu zaa zab zac zak zan zaz zbb zbc zce zea zeb zec zee zek zen zez zka znc zne znn zub zuc zuk zun zuz zzz