-er a-a a-c aaa aac aad aae aao aap aar ac- aca acc acd ace aco acp acr ad- ada adc add ade ado adp adr aea aec aed aee aeo aep aer aoa aoc aod aoe aoo aop aor ap- apa apc apd ape apo app apr ar- ara arc ard are aro arp arr c-- caa cac cad cae cao cap car cca ccc ccd cce cco ccp ccr cda cdc cdd cde cdo cdp cdr ce- cea cec ced cee ceo cep cer co- coa coc cod coe coo cop cor cpa cpc cpd cpe cpo cpp cpr cra crc crd cre cro crp crr daa dac dad dae dao dap dar dca dcc dcd dce dco dcp dcr dda ddc ddd dde ddo ddp ddr de- dea dec ded dee deo dep der doa doc dod doe doo dop dor dpa dpc dpd dpe dpo dpp dpr dra drc drd dre dro drp drr eaa eac ead eae eao eap ear ec- eca ecc ecd ece eco ecr ed- eda edc edd ede edo edp edr eea eec eed eee eeo eep eer eo- eoa eoc eod eoe eoo eop eor ep- epa epc epd epe epo epp epr era erc erd ere ero erp err oaa oac oad oae oao oap oar oc- oca occ ocd oco ocp ocr oda odc odd ode odo odp odr oea oec oed oee oeo oep oer oo- ooa ooc ood ooo oop oor op- opa opc opd ope opo opp opr or- ora orc ord ore oro orp orr p-p paa pac pad pae pao pap par pca pcc pcd pce pco pcp pcr pda pdc pdd pde pdo pdp pdr pea pec ped pee peo pep per poa poc pod poe poo pop por ppa ppc ppd ppe ppo ppp ppr pra prc prd pre pro prp prr ra- raa rac rad rae rao rap rar rca rcc rcd rce rco rcp rcr rda rdc rdd rde rdo rdp rdr re- rea rec red ree reo rep rer roa roc rod roe roo rop ror rpa rpc rpd rpe rpo rpp rpr rra rrc rrd rrp rrr