-er c-- ccc ccd cce cck ccn cco ccr cdc cdd cde cdk cdn cdo cdr ce- cec ced cee cek cen ceo cer ckc ckd cko cn- cnc cnd cne cnn cno cnr co- coc cod coe cok con coo cor crc crd cre crk crn cro crr dcc dcd dce dck dcn dco dcr ddc ddd dde ddk ddn ddo ddr de- dec ded dee dek den deo der dkc dke dkk dko dkr dnc dnd dne dnk dnn dno dnr doc dod doe dok don doo dor drc drd dre drk drn dro drr ec- ecc ecd ece eck ecn eco ecr ed- edc edd ede edk edn edo edr eec eed eee eek een eeo eer ekc ekd eke eko ekr en- enc end ene enk enn eno enr eo- eoc eod eoe eok eon eoo eor erc erd ere erk ern ero err kcc kcd kce kck kcn kcr kdc kde kdk kdo kdr ke- kec ked kee kek ken keo ker kkc kke kkk kkn kkr kn- knc knd kne knk knn kno knr koc kod koe kok kon koo kor krc krd krk krn kro krr ncc ncd nce nck ncn nco ncr ndc ndd nde ndk ndn ndo ndr ne- nec ned nee nek nen neo ner nkc nke nkk nkn nko nkr nnc nne nnk nnn nno no- noc nod noe nok non noo nor nrc nrd nre nrk nrn nro nrr oc- occ ocd ock ocn oco ocr odc odd ode odn odo odr oec oed oee oen oeo oer okc okd oke okk oko okr on- onc ond one onk onn ono onr oo- ooc ood ook oon ooo oor or- orc ord ore ork orn oro orr rcc rcd rce rcn rco rcr rdc rdd rde rdn rdo rdr re- rec red ree rek ren reo rer rkc rke rkk rko rnc rnd rnn rno rnr roc rod roe rok ron roo ror rrc rrd rrk rrn rrr