-al a-a a-b a-c aaa aab aac aae aaf aak aal aau ab- aba abb abc abe abf abk abl abu ac- aca acb acc ace acf ack acl acu aea aeb aec aee aef aek ael aeu af- afa afb afc afe aff afk afl afu aka akb akc ake akk akl aku al- ala alb alc ale alf alk all alu au- aua aub auc aue auf auk aul b-u baa bab bac bae baf bak bal bau bba bbb bbc bbe bbf bbk bbl bbu bca bcb bcc bce bcf bck bcl bcu be- bea beb bec bee bef bek bel beu bfa bfb bfc bfe bff bfl bfu bka bkb bkc bke bkf bkk bkl bla blb blc ble blf blk bll blu bua bub buc bue buf buk bul buu c-- caa cab cac cae caf cak cal cau cba cbb cbc cbe cbf cbk cbl cbu cca ccb ccc cce ccf cck ccl ccu ce- cea ceb cec cee cef cek cel ceu cfa cfb cfc cfe cff cfk cfl cfu cka ckb ckc cl- cla clb clc cle clf clk cll clu cua cub cuc cue cuf cuk cul cuu eaa eab eac eae eaf eak eal eau eba ebb ebc ebe ebf ebk ebl ebu ec- eca ecb ecc ece ecf eck ecl ecu eea eeb eec eee eef eek eel ef- efa efb efc efe eff efl eka ekb ekc eke ekf ekl eku ela elb elc ele elf elk ell elu eu- eua eub euc eue euf eul faa fab fac fae faf fak fal fau fba fbb fbc fbe fbf fbk fbl fbu fca fcb fcc fce fcf fck fcl fcu fea feb fec fee fef fek fel feu ffa ffc ffe fff ffk ffl ffu fka fkb fkc fkf fkk fkl fla flb flc fle flf fll flu fua fub fue fuf fuk ful fuu ka- kaa kab kac kae kaf kak kal kau kba kbb kbc kbe kbf kbk kbl kbu kca kcb kcc kce kck kcl kcu ke- kea keb kec kee kef kek kel kfa kfc kff kfu kkb kkc kke kkk kkl kku kl- kla klb klc klf klu kub kuc kue kuk kul kuu la- laa lab lac lae laf lak lal lau lba lbb lbc lbe lbf lbk lbl lbu lca lcb lcc lce lcf lck lcl lcu lea leb lec lee lef lek lel leu lfa lfb lfc lfe lff lfk lfl lfu lka lkb lkl lla llb llc lle llf llk lll llu lua lub luc lue luf luk lul luu ua- uaa uab uac uae uaf uak ual uau uba ubb ubc ube ubf ubk ubl ubu uca ucb ucc uce ucf uck ucl ucu uea ueb uec uee uef uel ufa ufc ufe uff ufl ufu uka ukb ukc uke ukf ukk ukl uku ula ulb ulc ule ulf ulk ull ulu uua uuc uue uuu