a-a a-b a-c aaa aab aac aad aae aak aan aau ab- aba abb abc abd abe abk abn abu ac- aca acb acc acd ace ack acn acu ad- ada adb adc add ade adk adn adu aea aeb aec aed aee aek aen aeu aka akb akc akd ake akk akn aku an- ana anb anc and ane ank ann anu au- aua aub auc aud aue auk aun b-u baa bab bac bad bae bak ban bau bba bbb bbc bbd bbe bbk bbn bbu bca bcb bcc bcd bce bck bcn bcu bda bdb bdc bdd bde bdk bdu be- bea beb bec bed bee bek ben beu bka bkb bkc bke bkk bkn bna bnb bnc bnd bne bnk bnn bnu bua bub buc bud bue buk bun buu c-- caa cab cac cad cae cak can cau cba cbb cbc cbd cbe cbk cbn cbu cca ccb ccc ccd cce cck ccn ccu cda cdb cdc cdd cde cdk cdn cdu ce- cea ceb cec ced cee cek cen ceu cka ckb ckc ckd cn- cna cnb cnc cnd cne cnn cnu cua cub cuc cud cue cuk cun cuu daa dab dac dad dae dak dan dau dba dbb dbc dbd dbe dbk dbn dbu dca dcb dcc dcd dce dck dcn dcu dda ddb ddc ddd dde ddk ddn ddu de- dea deb dec ded dee dek den deu dka dkb dkc dke dkk dku dna dnb dnc dnd dne dnk dnn dua dub duc dud due duk dun eaa eab eac ead eae eak ean eau eba ebb ebc ebd ebe ebk ebn ebu ec- eca ecb ecc ecd ece eck ecn ecu ed- eda edb edc edd ede edk edn edu eea eeb eec eed eee eek een eka ekb ekc ekd eke eku en- ena enb enc end ene enk enn enu eu- eua eub euc eud eue eun ka- kaa kab kac kad kae kak kan kau kba kbb kbc kbd kbe kbk kbn kbu kca kcb kcc kcd kce kck kcn kcu kda kdb kdc kde kdk kdu ke- kea keb kec ked kee kek ken kkb kkc kke kkk kkn kku kn- kna knc knd kne knk knn knu kub kuc kud kue kuk kun kuu naa nab nac nad nae nak nan nau nba nbb nbc nbd nbe nbk nbn nbu nca ncb ncc ncd nce nck ncn ncu nda ndb ndc ndd nde ndk ndn ndu ne- nea neb nec ned nee nek nen neu nka nkc nke nkk nkn nku nna nnb nnc nne nnk nnn nnu nua nub nuc nud nue nuk nun nuu ua- uaa uab uac uad uae uak uan uau uba ubb ubc ube ubk ubn ubu uca ucb ucc ucd uce uck ucn ucu uda udb udc udd ude udk udn udu uea ueb uec ued uee uen uka ukb ukc uke ukk ukn uku un- una unb unc und une unk unn unu uua uuc uue uun uuu