-al a-a a-b a-c a-t aaa aab aac aae aaf aak aal aat ab- aba abb abc abe abf abk abl abt ac- aca acb acc ace acf ack acl act aea aeb aec aee aef aek ael aet af- afa afb afc afe aff afk afl aft aka akb akc ake akk akl al- ala alb alc ale alf alk all alt at- ata atb atc ate atf atl att baa bab bac bae baf bak bal bat bba bbb bbc bbe bbf bbk bbl bbt bca bcb bcc bce bcf bck bcl bct be- bea beb bec bee bef bek bel bet bfa bfb bfc bfe bff bfl bft bka bkb bkc bke bkf bkk bkl bkt bla blb blc ble blf blk bll blt bta btb btc bte btf btk btl btt c-- caa cab cac cae caf cak cal cat cba cbb cbc cbe cbf cbk cbl cbt cca ccb ccc cce ccf cck ccl cct ce- cea ceb cec cee cef cek cel cet cfa cfb cfc cfe cff cfk cfl cft cka ckb ckc ckt cl- cla clb clc cle clf clk cll clt cta ctb ctc cte ctf ctk ctl ctt eaa eab eac eae eaf eak eal eat eba ebb ebc ebe ebf ebk ebl ebt ec- eca ecb ecc ece ecf eck ecl ect eea eeb eec eee eef eek eel eet ef- efa efb efc efe eff efl eft eka ekb ekc eke ekf ekl ekt ela elb elc ele elf elk ell elt eta etb etc ete etf etk etl ett faa fab fac fae faf fak fal fat fba fbb fbc fbe fbf fbk fbl fbt fca fcb fcc fce fcf fck fcl fct fea feb fec fee fef fek fel fet ffa ffc ffe fff ffk ffl fft fka fkb fkc fkf fkk fkl fkt fla flb flc fle flf fll flt fta ftb ftc fte ftf ftk ftl ftt k-t ka- kaa kab kac kae kaf kak kal kat kba kbb kbc kbe kbf kbk kbl kca kcb kcc kce kck kcl kct ke- kea keb kec kee kef kek kel ket kfa kfc kff kkb kkc kke kkk kkl kkt kl- kla klb klc klf klt kta ktb ktc kte ktf ktk ktl ktt la- laa lab lac lae laf lak lal lat lba lbb lbc lbe lbf lbk lbl lbt lca lcb lcc lce lcf lck lcl lct lea leb lec lee lef lek lel let lfa lfb lfc lfe lff lfk lfl lft lka lkb lkl lkt lla llb llc lle llf llk lll llt lta ltb ltc lte ltf ltk ltl ltt taa tab tac tae taf tak tal tat tba tbb tbc tbe tbf tbk tbl tbt tca tcb tcc tce tcf tck tcl tct te- tea teb tec tee tef tek tel tet tfa tfb tfc tfe tff tfk tfl tft tka tkb tkc tke tkk tkl tkt tla tlc tle tlf tlk tll tlt tta ttb ttc tte ttf ttk ttl ttt