-er a-a a-c aaa aac aae aaf aag aao aap aar ac- aca acc ace acf acg aco acp acr aea aec aee aef aeg aeo aep aer af- afa afc afe aff afg afo afp afr ag- aga agc age agf agg ago agp agr aoa aoc aoe aof aog aoo aop aor ap- apa apc ape apf apg apo app apr ar- ara arc are arf arg aro arp arr c-- caa cac cae caf cag cao cap car cca ccc cce ccf ccg cco ccp ccr ce- cea cec cee cef ceg ceo cep cer cfa cfc cfe cff cfg cfo cfp cfr cga cgc cge cgg cgo cgp cgr co- coa coc coe cof cog coo cop cor cpa cpc cpe cpf cpg cpo cpp cpr cra crc cre crf crg cro crp crr eaa eac eae eaf eag eao eap ear ec- eca ecc ece ecf ecg eco ecr eea eec eee eef eeg eeo eep eer ef- efa efc efe eff efg efo efp efr ega egc ege egf egg ego egp egr eo- eoa eoc eoe eof eog eoo eop eor ep- epa epc epe epf epg epo epp epr era erc ere erf erg ero erp err faa fac fae faf fag fao fap far fca fcc fce fcf fcg fco fcp fcr fea fec fee fef feg feo fep fer ffa ffc ffe fff ffg ffo ffp ffr fga fgc fge fgf fgg fgp fgr foa foc foe fof fog foo fop for fpa fpc fpe fpg fpo fpp fpr fra frc fre frf frg fro frp frr g-p gaa gac gae gaf gag gao gap gar gca gcc gce gcf gcg gco gcp gcr ge- gea gec gee gef geg geo gep ger gfa gfc gfe gff gfo gfp gfr gga ggc ggg ggo ggp ggr goa goc goe gof gog goo gop gor gpa gpc gpe gpf gpg gpo gpp gpr gra grc gre grf grg gro grp grr oaa oac oae oaf oag oao oap oar oc- oca occ ocf ocg oco ocp ocr oea oec oee oef oeg oeo oep oer of- ofa ofc ofe off ofg ofo ofp ofr oga ogc oge ogf ogg ogo ogp oo- ooa ooc oof oog ooo oop oor op- opa opc ope opf opg opo opp opr or- ora orc ore orf org oro orp orr p-p paa pac pae paf pag pao pap par pca pcc pce pcf pcg pco pcp pcr pea pec pee pef peg peo pep per pfa pfc pfe pff pfg pfo pfp pfr pga pgc pge pgf pgg pgo pgp pgr poa poc poe pof pog poo pop por ppa ppc ppe ppf ppg ppo ppp ppr pra prc pre prf prg pro prp prr ra- raa rac rae raf rag rao rap rar rca rcc rce rcf rcg rco rcp rcr re- rea rec ree ref reg reo rep rer rfa rfc rfe rff rfg rfo rfp rfr rga rgc rge rgf rgg rgo rgp rgr roa roc roe rof rog roo rop ror rpa rpc rpe rpf rpg rpo rpp rpr rra rrc rrf rrg rrp rrr