-th a-a a-c a-t aaa aac aae aah aat aax ac- aca acc ace ach act acx aea aec aee aeh aet aex aha ahc ahe ahh aht ahx at- ata atc ate ath att atx ax- axa axe axh axt axx c-- caa cac cae cah cat cax cca ccc cce cch cct ccx ce- cea cec cee ceh cet cex ch- cha chc che chh cht chx cta ctc cte cth ctt ctx cxc cxh cxt cxx eaa eac eae eah eat eax ec- eca ecc ece ech ect ecx eea eec eee eet eex eha ehc ehe ehh eht eta etc ete eth ett etx ex- exa exc exe exh ext exx haa hac hae hah hat hax hca hcc hce hch hct he- hea hec hee heh het hex hha hhc hhe hhh hht hta htc hte hth htt htx hxc t-x taa tac tae tah tat tax tca tcc tce tch tct tcx te- tea tec tee teh tet tex th- tha thc the thh tht thx tta ttc tte tth ttt ttx txe txt xaa xac xat xch xcx xee xet xex xht xtc xtx xxx