-er a-a a-b aaa aab aad aae aaf aao aap aar ab- aba abb abd abe abf abo abp abr ad- ada adb add ade adf ado adp adr aea aeb aed aee aef aeo aep aer af- afa afb afd afe aff afo afp afr aoa aob aod aoe aof aoo aop aor ap- apa apb apd ape apf apo app apr ar- ara arb ard are arf aro arp arr b-p baa bab bad bae baf bao bap bar bba bbb bbd bbe bbf bbo bbp bbr bda bdb bdd bde bdf bdo bdp bdr be- bea beb bed bee bef beo bep ber bfa bfb bfd bfe bff bfo bfp bfr boa bob bod boe bof boo bop bor bpa bpb bpd bpe bpf bpo bpp bpr bra brb brd bre brf bro brp brr daa dab dad dae daf dao dap dar dba dbb dbd dbe dbf dbo dbp dbr dda ddb ddd dde ddf ddo ddp ddr de- dea deb ded dee def deo dep der dfa dfb dfd dfe dff dfo dfp dfr doa dob dod doe dof doo dop dor dpa dpb dpd dpe dpf dpo dpp dpr dra drb drd dre dro drp drr eaa eab ead eae eaf eao eap ear eba ebb ebd ebe ebf ebo ebp ebr ed- eda edb edd ede edf edo edp edr eea eeb eed eee eef eeo eep eer ef- efa efb efd efe eff efo efp efr eo- eoa eob eod eoe eof eoo eop eor ep- epa epb epd epe epf epo epp epr era erb erd ere erf ero erp err faa fab fad fae faf fao fap far fba fbb fbd fbe fbf fbo fbp fbr fda fdb fdd fde fdf fdo fdp fdr fea feb fed fee fef feo fep fer ffa ffd ffe fff ffo ffp ffr foa fob foe fof foo fop for fpa fpb fpd fpe fpo fpp fpr fra frb frd fre frf fro frp frr oaa oab oad oae oaf oao oap oar ob- oba obb obd obe obf obo obp obr oda odb odd ode odf odo odp odr oea oeb oed oee oef oeo oep oer of- ofa ofb ofd ofe off ofo ofp ofr oo- ooa oob ood oof ooo oop oor op- opa opb opd ope opf opo opp opr or- ora orb ord ore orf oro orp orr p-p paa pab pad pae paf pao pap par pba pbb pbd pbe pbf pbo pbp pbr pda pdb pdd pde pdf pdo pdp pdr pea peb ped pee pef peo pep per pfa pfb pfd pfe pff pfo pfp pfr poa pob pod poe pof poo pop por ppa ppb ppd ppe ppf ppo ppp ppr pra prb prd pre prf pro prp prr ra- raa rab rad rae raf rao rap rar rba rbb rbd rbe rbf rbo rbp rbr rda rdb rdd rde rdf rdo rdp rdr re- rea reb red ree ref reo rep rer rfa rfb rfd rfe rff rfo rfp rfr roa rob rod roe rof roo rop ror rpa rpb rpd rpe rpf rpo rpp rpr rra rrb rrd rrf rrp rrr