-er a-a a-b aaa aab aad aae aao aap aar aas ab- aba abb abd abe abo abp abr abs ad- ada adb add ade ado adp adr ads aea aeb aed aee aeo aep aer aes aoa aob aod aoe aoo aop aor aos ap- apa apb apd ape apo app apr aps ar- ara arb ard are aro arp arr ars as- asa asb asd ase aso asp asr ass b-p baa bab bad bae bao bap bar bas bba bbb bbd bbe bbo bbp bbr bbs bda bdb bdd bde bdo bdp bdr bds be- bea beb bed bee beo bep ber bes boa bob bod boe boo bop bor bos bpa bpb bpd bpe bpo bpp bpr bps bra brb brd bre bro brp brr brs bsa bsb bsd bse bso bsp bsr bss daa dab dad dae dao dap dar das dba dbb dbd dbe dbo dbp dbr dbs dda ddb ddd dde ddo ddp ddr dds de- dea deb ded dee deo dep der des doa dob dod doe doo dop dor dos dpa dpb dpd dpe dpo dpp dpr dps dra drb drd dre dro drp drr drs dsa dsb dsd dse dso dsp dsr dss eaa eab ead eae eao eap ear eas eba ebb ebd ebe ebo ebp ebr ebs ed- eda edb edd ede edo edp edr eds eea eeb eed eee eeo eep eer ees eo- eoa eob eod eoe eoo eop eor eos ep- epa epb epd epe epo epp epr eps era erb erd ere ero erp err ers es- esa esb esd ese eso esp esr ess oaa oab oad oae oao oap oar oas ob- oba obb obd obe obo obp obr obs oda odb odd ode odo odp odr ods oea oeb oed oee oeo oep oer oes oo- ooa oob ood ooo oop oor oos op- opa opb opd ope opo opp opr ops or- ora orb ord ore oro orp orr ors os- osa osb osd ose oso osp osr oss p-p paa pab pad pae pao pap par pas pba pbb pbd pbe pbo pbp pbr pbs pda pdb pdd pde pdo pdp pdr pds pea peb ped pee peo pep per pes poa pob pod poe poo pop por pos ppa ppb ppd ppe ppo ppp ppr pps pra prb prd pre pro prp prr prs ps- psa psb psd pse pso psp psr pss ra- raa rab rad rae rao rap rar ras rba rbb rbd rbe rbo rbp rbr rbs rda rdb rdd rde rdo rdp rdr rds re- rea reb red ree reo rep rer res roa rob rod roe roo rop ror ros rpa rpb rpd rpe rpo rpp rpr rps rra rrb rrd rrp rrr rrs rsa rsb rsd rse rso rsp rsr rss saa sab sad sae sao sap sar sas sba sbb sbd sbe sbo sbp sbr sbs sda sdb sdd sde sdo sdp sdr sds se- sea seb sed see seo sep ser ses soa sob sod soe soo sop sor sos spa spb spd spe spo spp spr sps sr- sra srb srd sre sro srp srr srs ss- ssa ssb ssd sse sso ssp ssr sss