-er a-a a-c aaa aac aae aan aar ac- aca acc ace acn acr aea aec aee aen aer an- ana anc ane ann anr ar- ara arc are arn arr c-- caa cac cae can car cca ccc cce ccn ccr ce- cea cec cee cen cer cn- cna cnc cne cnn cnr cra crc cre crn crr eaa eac eae ean ear ec- eca ecc ece ecn ecr eea eec eee een eer en- ena enc ene enn enr era erc ere ern err naa nac nae nan nar nca ncc nce ncn ncr ne- nea nec nee nen ner nna nnc nne nnn nra nrc nre nrn nrr ra- raa rac rae ran rar rca rcc rce rcn rcr re- rea rec ree ren rer rna rnc rnn rnr rra rrc rrn rrr