a-a a-c aaa aac aad aan aas ac- aca acc acd acn acs ad- ada adc add adn ads an- ana anc and ann ans as- asa asc asd asn ass c-- caa cac cad can cas cca ccc ccd ccn ccs cda cdc cdd cdn cds cn- cna cnc cnd cnn cns csa csc csd csn css daa dac dad dan das dca dcc dcd dcn dcs dda ddc ddd ddn dds dna dnc dnd dnn dns dsa dsc dsd dsn dss naa nac nad nan nas nca ncc ncd ncn ncs nda ndc ndd ndn nds nna nnc nnn nns nsa nsc nsd nsn nss saa sac sad san sas sca scc scd scn scs sda sdc sdd sdn sds sna snc snd snn sns ss- ssa ssc ssd ssn sss