c-- ccc cce cco ccp ccs ccx ce- cec cee ceo cep ces cex co- coc coe coo cop cos cox cpc cpe cpo cpp cps cpx csc cse cso csp css csx cxc cxo cxp cxs cxx ec- ecc ece eco ecs ecx eec eee eeo eep ees eex eo- eoc eoe eoo eop eos ep- epc epe epo epp eps epx es- esc ese eso esp ess esx ex- exc exe exo exp exs exx oc- occ oco ocp ocs ocx oec oee oeo oep oes oex oo- ooc ooo oop oos oox op- opc ope opo opp ops opx os- osc ose oso osp oss osx ox- oxc oxo oxx p-p pcc pce pco pcp pcs pcx pec pee peo pep pes pex poc poe poo pop pos pox ppc ppe ppo ppp pps ppx ps- psc pse pso psp pss psx pxc pxe pxs scc sce sco scp scs scx se- sec see seo sep ses sex soc soe soo sop sos sox spc spe spo spp sps spx ss- ssc sse sso ssp sss ssx sxc sxs xcp xcx xee xep xes xex xoc xoo xop xos xox xpc xpe xpo xpp xps xsc xsp xss xxo xxp xxx