a-a a-c aaa aac aae aao aap aas aax ac- aca acc ace aco acp acs acx aea aec aee aeo aep aes aex aoa aoc aoe aoo aop aos aox ap- apa apc ape apo app aps apx as- asa asc ase aso asp ass asx ax- axa axe axo axp axs axx c-- caa cac cae cao cap cas cax cca ccc cce cco ccp ccs ccx ce- cea cec cee ceo cep ces cex co- coa coc coe coo cop cos cox cpa cpc cpe cpo cpp cps cpx csa csc cse cso csp css csx cxc cxo cxp cxs cxx eaa eac eae eao eap eas eax ec- eca ecc ece eco ecs ecx eea eec eee eeo eep ees eex eo- eoa eoc eoe eoo eop eos ep- epa epc epe epo epp eps epx es- esa esc ese eso esp ess esx ex- exa exc exe exo exp exs exx oaa oac oae oao oap oas oax oc- oca occ oco ocp ocs ocx oea oec oee oeo oep oes oex oo- ooa ooc ooo oop oos oox op- opa opc ope opo opp ops opx os- osa osc ose oso osp oss osx ox- oxa oxc oxo oxx p-p paa pac pae pao pap pas pax pca pcc pce pco pcp pcs pcx pea pec pee peo pep pes pex poa poc poe poo pop pos pox ppa ppc ppe ppo ppp pps ppx ps- psa psc pse pso psp pss psx pxc pxe pxs saa sac sae sao sap sas sax sca scc sce sco scp scs scx se- sea sec see seo sep ses sex soa soc soe soo sop sos sox spa spc spe spo spp sps spx ss- ssa ssc sse sso ssp sss ssx sxc sxs xaa xac xap xas xcp xcx xee xep xes xex xoa xoc xoo xop xos xox xpa xpc xpe xpo xpp xps xsa xsc xsp xss xxo xxp xxx