-er ddd dde ddf ddi ddo ddp ddr ddx de- ded dee def dei deo dep der dex dfd dfe dff dfi dfo dfp dfr dfx di- did die dif dii dio dip dir dix dod doe dof doi doo dop dor dox dpd dpe dpf dpi dpo dpp dpr drd dre dri dro drp drr drx dxd dxi dxo dxp dxr dxx ed- edd ede edf edi edo edp edr edx eed eee eef eeo eep eer eex ef- efd efe eff efi efo efp efr efx eid eie eif eii eio eip eir eix eo- eod eoe eof eoi eoo eop eor ep- epd epe epf epi epo epp epr epx erd ere erf eri ero erp err ex- exd exe exi exo exp exr exx fdd fde fdf fdi fdo fdp fdr fdx fed fee fef fei feo fep fer fex ffd ffe fff ffi ffo ffp ffr ffx fid fie fif fii fip fir fix foe fof foi foo fop for fox fpd fpe fpi fpo fpp fpr fpx frd fre frf fri fro frp frr fxe fxi fxp fxr fxx i-d i-f idd ide idf idi ido idp idr idx ie- ied iee ief iei iep ier iex ifd ife iff ifi ifo ifp ifr ifx iid iie iif iii iio iip iir iix io- iod ioe iof ioi ioo iop ior ipd ipe ipf ipi ipo ipp ipr ipx ir- ird ire irf iri iro irp irr irx ixe ixi o-i odd ode odf odi odo odp odr oed oee oef oei oeo oep oer oex of- ofd ofe off ofi ofo ofp ofr ofx oid oie oif oii oio oip oir oo- ood oof ooi ooo oop oor oox op- opd ope opf opi opo opp opr opx or- ord ore orf ori oro orp orr orx ox- oxf oxi oxo oxx p-p pdd pde pdf pdi pdo pdp pdr pdx ped pee pef pei peo pep per pex pfd pfe pff pfi pfo pfp pfr pfx pid pie pif pii pio pip pir pix pod poe pof poi poo pop por pox ppd ppe ppf ppi ppo ppp ppr ppx prd pre prf pri pro prp prr prx pxe pxr rdd rde rdf rdi rdo rdp rdr rdx re- red ree ref rei reo rep rer rex rfd rfe rff rfi rfo rfp rfr rid rie rif rii rio rip rir rix rod roe rof roi roo rop ror rox rpd rpe rpf rpi rpo rpp rpr rpx rrd rrf rri rrp rrr rxp rxr xde xdf xdi xdr xed xee xep xer xex xfe xfx xie xii xio xix xod xof xoi xoo xop xor xox xpd xpe xpf xpo xpp xrd xrf xrx xxi xxo xxp xxx