a-a a-c aaa aac aae aaf aao aap aas ac- aca acc ace acf aco acp acs aea aec aee aef aeo aep aes af- afa afc afe aff afo afp afs aoa aoc aoe aof aoo aop aos ap- apa apc ape apf apo app aps as- asa asc ase asf aso asp ass c-- caa cac cae caf cao cap cas cca ccc cce ccf cco ccp ccs ce- cea cec cee cef ceo cep ces cfa cfc cfe cff cfo cfp cfs co- coa coc coe cof coo cop cos cpa cpc cpe cpf cpo cpp cps csa csc cse csf cso csp css eaa eac eae eaf eao eap eas ec- eca ecc ece ecf eco ecs eea eec eee eef eeo eep ees ef- efa efc efe eff efo efp efs eo- eoa eoc eoe eof eoo eop eos ep- epa epc epe epf epo epp eps es- esa esc ese esf eso esp ess faa fac fae faf fao fap fas fca fcc fce fcf fco fcp fcs fea fec fee fef feo fep fes ffa ffc ffe fff ffo ffp ffs foa foc foe fof foo fop fos fpa fpc fpe fpo fpp fps fsa fsc fse fsf fso fsp fss oaa oac oae oaf oao oap oas oc- oca occ ocf oco ocp ocs oea oec oee oef oeo oep oes of- ofa ofc ofe off ofo ofp ofs oo- ooa ooc oof ooo oop oos op- opa opc ope opf opo opp ops os- osa osc ose osf oso osp oss p-p paa pac pae paf pao pap pas pca pcc pce pcf pco pcp pcs pea pec pee pef peo pep pes pfa pfc pfe pff pfo pfp pfs poa poc poe pof poo pop pos ppa ppc ppe ppf ppo ppp pps ps- psa psc pse psf pso psp pss saa sac sae saf sao sap sas sca scc sce scf sco scp scs se- sea sec see sef seo sep ses sfa sfc sfe sff sfo sfp sfs soa soc soe sof soo sop sos spa spc spe spf spo spp sps ss- ssa ssc sse ssf sso ssp sss