-er bbb bbc bbd bbe bbn bbo bbr bbs bcb bcc bcd bce bcn bco bcr bcs bdb bdc bdd bde bdo bdr bds be- beb bec bed bee ben beo ber bes bnb bnc bnd bne bnn bno bnr bns bob boc bod boe bon boo bor bos brb brd bre brn bro brr brs bsb bsc bsd bse bsn bso bsr bss c-- cbb cbc cbd cbe cbn cbo cbr cbs ccb ccc ccd cce ccn cco ccr ccs cdb cdc cdd cde cdn cdo cdr cds ce- ceb cec ced cee cen ceo cer ces cn- cnb cnc cnd cne cnn cno cnr cns co- cob coc cod coe con coo cor cos crb crc crd cre crn cro crr crs csb csc csd cse csn cso csr css dbb dbc dbd dbe dbn dbo dbr dbs dcb dcc dcd dce dcn dco dcr dcs ddb ddc ddd dde ddn ddo ddr dds de- deb dec ded dee den deo der des dnb dnc dnd dne dnn dno dnr dns dob doc dod doe don doo dor dos drb drc drd dre drn dro drr drs dsb dsc dsd dse dsn dso dsr dss ebb ebc ebd ebe ebn ebo ebr ebs ec- ecb ecc ecd ece ecn eco ecr ecs ed- edb edc edd ede edn edo edr eds eeb eec eed eee een eeo eer ees en- enb enc end ene enn eno enr ens eo- eob eoc eod eoe eon eoo eor eos erb erc erd ere ern ero err ers es- esb esc esd ese esn eso esr ess nbb nbc nbd nbe nbn nbo nbr nbs ncb ncc ncd nce ncn nco ncr ncs ndb ndc ndd nde ndn ndo ndr nds ne- neb nec ned nee nen neo ner nes nnb nnc nne nnn nno nns no- nob noc nod noe non noo nor nos nrb nrc nrd nre nrn nro nrr nrs nsb nsc nsd nse nsn nso nsr nss ob- obb obc obd obe obn obo obr obs oc- ocb occ ocd ocn oco ocr ocs odb odc odd ode odn odo odr ods oeb oec oed oee oen oeo oer oes on- onb onc ond one onn ono onr ons oo- oob ooc ood oon ooo oor oos or- orb orc ord ore orn oro orr ors os- osb osc osd ose osn oso osr oss rbb rbc rbd rbe rbn rbo rbr rbs rcb rcc rcd rce rcn rco rcr rcs rdb rdc rdd rde rdn rdo rdr rds re- reb rec red ree ren reo rer res rnb rnc rnd rnn rno rnr rns rob roc rod roe ron roo ror ros rrb rrc rrd rrn rrr rrs rsb rsc rsd rse rsn rso rsr rss sbb sbc sbd sbe sbn sbo sbr sbs scb scc scd sce scn sco scr scs sdb sdc sdd sde sdn sdo sdr sds se- seb sec sed see sen seo ser ses snb snc snd sne snn sno snr sns sob soc sod soe son soo sor sos sr- srb src srd sre srn sro srr srs ss- ssb ssc ssd sse ssn sso ssr sss