-er c-- ccc cce ccg cco ccr cct ce- cec cee ceg ceo cer cet cgc cge cgg cgo cgr cgt co- coc coe cog coo cor cot crc cre crg cro crr crt ctc cte ctg cto ctr ctt ec- ecc ece ecg eco ecr ect eec eee eeg eeo eer eet egc ege egg ego egr egt eo- eoc eoe eog eoo eor eot erc ere erg ero err ert etc ete etg eto etr ett gcc gce gcg gco gcr gct ge- gec gee geg geo ger get ggc ggg ggo ggr ggt goc goe gog goo gor got grc gre grg gro grr grt gtc gte gtg gto gtr gtt oc- occ ocg oco ocr oct oec oee oeg oeo oer oet ogc oge ogg ogo ogt oo- ooc oog ooo oor oot or- orc ore org oro orr ort ot- otc ote otg oto otr ott rcc rce rcg rco rcr rct re- rec ree reg reo rer ret rgc rge rgg rgo rgr rgt roc roe rog roo ror rot rrc rrg rrr rrt rtc rte rtg rto rtr rtt tcc tce tcg tco tcr tct te- tec tee teg teo ter tet tgc tge tgg tgo tgr tgt to- toc toe tog too tor tot trc tre trg tro trr trt ttc tte ttg tto ttr ttt