-er c-- ccc cce ccg ccr ccs cct ce- cec cee ceg cer ces cet cgc cge cgg cgr cgs cgt crc cre crg crr crs crt csc cse csg csr css cst ctc cte ctg ctr cts ctt ec- ecc ece ecg ecr ecs ect eec eee eeg eer ees eet egc ege egg egr egs egt erc ere erg err ers ert es- esc ese esg esr ess est etc ete etg etr ets ett gcc gce gcg gcr gcs gct ge- gec gee geg ger ges get ggc ggg ggr ggs ggt grc gre grg grr grs grt gsc gse gsg gsr gss gst gtc gte gtg gtr gts gtt rcc rce rcg rcr rcs rct re- rec ree reg rer res ret rgc rge rgg rgr rgs rgt rrc rrg rrr rrs rrt rsc rse rsg rsr rss rst rtc rte rtg rtr rts rtt scc sce scg scr scs sct se- sec see seg ser ses set sgc sge sgg sgr sgs sgt sr- src sre srg srr srs srt ss- ssc sse ssg ssr sss sst stc ste stg str sts stt tcc tce tcg tcr tcs tct te- tec tee teg ter tes tet tgc tge tgg tgr tgs tgt trc tre trg trr trs trt tsc tse tsg tsr tss tst ttc tte ttg ttr tts ttt