a-a a-b a-c a-t aaa aab aac aae aaf aat aau ab- aba abb abc abe abf abt abu ac- aca acb acc ace acf act acu aea aeb aec aee aef aet aeu af- afa afb afc afe aff aft afu at- ata atb atc ate atf att atu au- aua aub auc aue auf aut b-u baa bab bac bae baf bat bau bba bbb bbc bbe bbf bbt bbu bca bcb bcc bce bcf bct bcu be- bea beb bec bee bef bet beu bfa bfb bfc bfe bff bft bfu bta btb btc bte btf btt btu bua bub buc bue buf but buu c-- caa cab cac cae caf cat cau cba cbb cbc cbe cbf cbt cbu cca ccb ccc cce ccf cct ccu ce- cea ceb cec cee cef cet ceu cfa cfb cfc cfe cff cft cfu cta ctb ctc cte ctf ctt ctu cua cub cuc cue cuf cut cuu eaa eab eac eae eaf eat eau eba ebb ebc ebe ebf ebt ebu ec- eca ecb ecc ece ecf ect ecu eea eeb eec eee eef eet ef- efa efb efc efe eff eft eta etb etc ete etf ett etu eu- eua eub euc eue euf eut faa fab fac fae faf fat fau fba fbb fbc fbe fbf fbt fbu fca fcb fcc fce fcf fct fcu fea feb fec fee fef fet feu ffa ffc ffe fff fft ffu fta ftb ftc fte ftf ftt ftu fua fub fue fuf fut fuu taa tab tac tae taf tat tau tba tbb tbc tbe tbf tbt tbu tca tcb tcc tce tcf tct tcu te- tea teb tec tee tef tet teu tfa tfb tfc tfe tff tft tfu tta ttb ttc tte ttf ttt ttu tua tub tuc tue tuf tut tuu ua- uaa uab uac uae uaf uat uau uba ubb ubc ube ubf ubt ubu uca ucb ucc uce ucf uct ucu uea ueb uec uee uef uet ufa ufc ufe uff uft ufu uta utb utc ute utf utt utu uua uuc uue uut uuu