-er bbb bbc bbd bbe bbf bbm bbo bbr bcb bcc bcd bce bcf bcm bco bcr bdb bdc bdd bde bdf bdm bdo bdr be- beb bec bed bee bef bem beo ber bfb bfc bfd bfe bff bfm bfo bfr bmb bmc bmd bme bmf bmm bmo bmr bob boc bod boe bof bom boo bor brb brd bre brf brm bro brr c-- cbb cbc cbd cbe cbf cbm cbo cbr ccb ccc ccd cce ccf ccm cco ccr cdb cdc cdd cde cdf cdm cdo cdr ce- ceb cec ced cee cef cem ceo cer cfb cfc cfd cfe cff cfm cfo cfr cmb cmc cmd cme cmf cmm cmo cmr co- cob coc cod coe cof com coo cor crb crc crd cre crf crm cro crr dbb dbc dbd dbe dbf dbm dbo dbr dcb dcc dcd dce dcf dcm dco dcr ddb ddc ddd dde ddf ddm ddo ddr de- deb dec ded dee def dem deo der dfb dfc dfd dfe dff dfm dfo dfr dmb dmc dmd dme dmf dmm dmo dmr dob doc dod doe dof dom doo dor drb drc drd dre drm dro drr ebb ebc ebd ebe ebf ebm ebo ebr ec- ecb ecc ecd ece ecf ecm eco ecr ed- edb edc edd ede edf edm edo edr eeb eec eed eee eef eem eeo eer ef- efb efc efd efe eff efm efo efr em- emb emc emd eme emf emm emo emr eo- eob eoc eod eoe eof eom eoo eor erb erc erd ere erf erm ero err fbb fbc fbd fbe fbf fbm fbo fbr fcb fcc fcd fce fcf fcm fco fcr fdb fdc fdd fde fdf fdm fdo fdr feb fec fed fee fef fem feo fer ffc ffd ffe fff ffm ffo ffr fmb fmc fmd fme fmf fmm fmo fmr fob foc foe fof fom foo for frb frc frd fre frf frm fro frr m-f m-o m-r mbb mbc mbd mbe mbf mbm mbo mbr mc- mcb mcc mcd mce mcf mcm mco mcr mdb mdc mdd mde mdf mdm mdo mdr meb mec med mee mef mem meo mer mfb mfc mfd mfe mff mfm mfo mfr mmb mmc mmd mme mmf mmm mmo mmr mob moc mod moe mof mom moo mor mrb mrc mrd mre mrf mrm mro mrr ob- obb obc obd obe obf obm obo obr oc- ocb occ ocd ocf ocm oco ocr odb odc odd ode odf odm odo odr oeb oec oed oee oef oem oeo oer of- ofb ofc ofd ofe off ofm ofo ofr om- omb omc omd ome omf omm omo omr oo- oob ooc ood oof oom ooo oor or- orb orc ord ore orf orm oro orr rbb rbc rbd rbe rbf rbm rbo rbr rcb rcc rcd rce rcf rcm rco rcr rdb rdc rdd rde rdf rdm rdo rdr re- reb rec red ree ref rem reo rer rfb rfc rfd rfe rff rfm rfo rfr rmb rmc rmd rme rmf rmm rmo rmr rob roc rod roe rof rom roo ror rrb rrc rrd rrf rrm rrr