c-- ccc cce ccn ccp ccs ccx ce- cec cee cen cep ces cex cn- cnc cne cnn cnp cns cnx cpc cpe cpn cpp cps cpx csc cse csn csp css csx cxc cxp cxs cxx ec- ecc ece ecn ecs ecx eec eee een eep ees eex en- enc ene enn enp ens ep- epc epe epn epp eps epx es- esc ese esn esp ess esx ex- exc exe exp exs exx ncc nce ncn ncp ncs ncx ne- nec nee nen nep nes nex nnc nne nnn nnp nns npc npe npn npp nps nsc nse nsn nsp nss nsx nxc p-p pcc pce pcn pcp pcs pcx pec pee pen pep pes pex pn- pnc pne pnn pnp pns pnx ppc ppe ppn ppp pps ppx ps- psc pse psn psp pss psx pxc pxe pxs scc sce scn scp scs scx se- sec see sen sep ses sex snc sne snn snp sns spc spe spn spp sps spx ss- ssc sse ssn ssp sss ssx sxc sxn sxs xcp xcx xee xen xep xes xex xnc xns xpc xpe xpn xpp xps xsc xsp xss xxp xxx