a-a a-c aaa aac aae aam aax ac- aca acc ace acm acx aea aec aee aem aex ama amc ame amm amx ax- axa axe axm axx c-- caa cac cae cam cax cca ccc cce ccm ccx ce- cea cec cee cem cex cma cmc cme cmm cmx cxc cxx eaa eac eae eam eax ec- eca ecc ece ecm ecx eea eec eee eem eex em- ema emc eme emm emx ex- exa exc exe exx maa mac mae mam max mc- mca mcc mce mcm mcx mea mec mee mem mex mma mmc mme mmm mmx mxa mxc xaa xac xam xcx xee xem xex xma xmc xmm xmx xxx