a-a a-c aaa aac aae aak aao aap aas ac- aca acc ace ack aco acp acs aea aec aee aek aeo aep aes aka akc ake akk ako akp aks aoa aoc aoe aok aoo aop aos ap- apa apc ape apk apo app aps as- asa asc ase ask aso asp ass c-- caa cac cae cak cao cap cas cca ccc cce cck cco ccp ccs ce- cea cec cee cek ceo cep ces cka ckc cko cks co- coa coc coe cok coo cop cos cpa cpc cpe cpk cpo cpp cps csa csc cse csk cso csp css eaa eac eae eak eao eap eas ec- eca ecc ece eck eco ecs eea eec eee eek eeo eep ees eka ekc eke eko ekp eks eo- eoa eoc eoe eok eoo eop eos ep- epa epc epe epo epp eps es- esa esc ese esk eso esp ess ka- kaa kac kae kak kao kap kas kca kcc kce kck kcp kcs ke- kea kec kee kek keo kep kes kkc kke kkk kkp kks koa koc koe kok koo kop kos kpa kpc kpe kpk kpo kpp kps ksa ksc kse ksk kso ksp kss oaa oac oae oak oao oap oas oc- oca occ ock oco ocp ocs oea oec oee oeo oep oes oka okc oke okk oko okp oks oo- ooa ooc ook ooo oop oos op- opa opc ope opk opo opp ops os- osa osc ose osk oso osp oss p-p paa pac pae pak pao pap pas pca pcc pce pck pco pcp pcs pea pec pee pek peo pep pes pka pkc pke pko pkp pks poa poc poe pok poo pop pos ppa ppc ppe ppk ppo ppp pps ps- psa psc pse psk pso psp pss saa sac sae sak sao sap sas sca scc sce sck sco scp scs se- sea sec see sek seo sep ses sk- ska skc ske skk sko skp sks soa soc soe sok soo sop sos spa spc spe spk spo spp sps ss- ssa ssc sse ssk sso ssp sss