-er ddd dde ddf ddo ddp ddr de- ded dee def deo dep der dfd dfe dff dfo dfp dfr dod doe dof doo dop dor dpd dpe dpf dpo dpp dpr drd dre dro drp drr ed- edd ede edf edo edp edr eed eee eef eeo eep eer ef- efd efe eff efo efp efr eo- eod eoe eof eoo eop eor ep- epd epe epf epo epp epr erd ere erf ero erp err fdd fde fdf fdo fdp fdr fed fee fef feo fep fer ffd ffe fff ffo ffp ffr foe fof foo fop for fpd fpe fpo fpp fpr frd fre frf fro frp frr odd ode odf odo odp odr oed oee oef oeo oep oer of- ofd ofe off ofo ofp ofr oo- ood oof ooo oop oor op- opd ope opf opo opp opr or- ord ore orf oro orp orr p-p pdd pde pdf pdo pdp pdr ped pee pef peo pep per pfd pfe pff pfo pfp pfr pod poe pof poo pop por ppd ppe ppf ppo ppp ppr prd pre prf pro prp prr rdd rde rdf rdo rdp rdr re- red ree ref reo rep rer rfd rfe rff rfo rfp rfr rod roe rof roo rop ror rpd rpe rpf rpo rpp rpr rrd rrf rrp rrr