-er a-a a-c aaa aac aae aam aar ac- aca acc ace acm acr aea aec aee aem aer ama amc ame amm amr ar- ara arc are arm arr c-- caa cac cae cam car cca ccc cce ccm ccr ce- cea cec cee cem cer cma cmc cme cmm cmr cra crc cre crm crr eaa eac eae eam ear ec- eca ecc ece ecm ecr eea eec eee eem eer em- ema emc eme emm emr era erc ere erm err m-r maa mac mae mam mar mc- mca mcc mce mcm mcr mea mec mee mem mer mma mmc mme mmm mmr mra mrc mre mrm mrr ra- raa rac rae ram rar rca rcc rce rcm rcr re- rea rec ree rem rer rma rmc rme rmm rmr rra rrc rrm rrr