-er b-p bbb bbc bbd bbe bbo bbp bbr bcb bcc bcd bce bco bcp bcr bdb bdc bdd bde bdo bdp bdr be- beb bec bed bee beo bep ber bob boc bod boe boo bop bor bpb bpc bpd bpe bpo bpp bpr brb brd bre bro brp brr c-- cbb cbc cbd cbe cbo cbp cbr ccb ccc ccd cce cco ccp ccr cdb cdc cdd cde cdo cdp cdr ce- ceb cec ced cee ceo cep cer co- cob coc cod coe coo cop cor cpb cpc cpd cpe cpo cpp cpr crb crc crd cre cro crp crr dbb dbc dbd dbe dbo dbp dbr dcb dcc dcd dce dco dcp dcr ddb ddc ddd dde ddo ddp ddr de- deb dec ded dee deo dep der dob doc dod doe doo dop dor dpb dpc dpd dpe dpo dpp dpr drb drc drd dre dro drp drr ebb ebc ebd ebe ebo ebp ebr ec- ecb ecc ecd ece eco ecr ed- edb edc edd ede edo edp edr eeb eec eed eee eeo eep eer eo- eob eoc eod eoe eoo eop eor ep- epb epc epd epe epo epp epr erb erc erd ere ero erp err ob- obb obc obd obe obo obp obr oc- ocb occ ocd oco ocp ocr odb odc odd ode odo odp odr oeb oec oed oee oeo oep oer oo- oob ooc ood ooo oop oor op- opb opc opd ope opo opp opr or- orb orc ord ore oro orp orr p-p pbb pbc pbd pbe pbo pbp pbr pcb pcc pcd pce pco pcp pcr pdb pdc pdd pde pdo pdp pdr peb pec ped pee peo pep per pob poc pod poe poo pop por ppb ppc ppd ppe ppo ppp ppr prb prc prd pre pro prp prr rbb rbc rbd rbe rbo rbp rbr rcb rcc rcd rce rco rcp rcr rdb rdc rdd rde rdo rdp rdr re- reb rec red ree reo rep rer rob roc rod roe roo rop ror rpb rpc rpd rpe rpo rpp rpr rrb rrc rrd rrp rrr