a-a a-c aaa aac aae aas aau aax ac- aca acc ace acs acu acx aea aec aee aes aeu aex as- asa asc ase ass asu asx au- aua auc aue aus aux ax- axa axe axs axx c-- caa cac cae cas cau cax cca ccc cce ccs ccu ccx ce- cea cec cee ces ceu cex csa csc cse css csu csx cua cuc cue cus cuu cxc cxs cxx eaa eac eae eas eau eax ec- eca ecc ece ecs ecu ecx eea eec eee ees eex es- esa esc ese ess esu esx eu- eua euc eue eus eux ex- exa exc exe exs exu exx saa sac sae sas sau sax sca scc sce scs scu scx se- sea sec see ses seu sex ss- ssa ssc sse sss ssu ssx sua suc sue sus suu sux sxc sxs sxu ua- uaa uac uae uas uau uca ucc uce ucs ucu uea uec uee ues usa usc use uss usu usx uua uuc uue uus uuu uxc uxu xaa xac xas xau xcx xee xes xeu xex xsa xsc xss xue xus xxx