a-a a-c aaa aac aad aar aas ac- aca acc acd acr acs ad- ada adc add adr ads ar- ara arc ard arr ars as- asa asc asd asr ass c-- caa cac cad car cas cca ccc ccd ccr ccs cda cdc cdd cdr cds cra crc crd crr crs csa csc csd csr css daa dac dad dar das dca dcc dcd dcr dcs dda ddc ddd ddr dds dra drc drd drr drs dsa dsc dsd dsr dss ra- raa rac rad rar ras rca rcc rcd rcr rcs rda rdc rdd rdr rds rra rrc rrd rrr rrs rsa rsc rsd rsr rss saa sac sad sar sas sca scc scd scr scs sda sdc sdd sdr sds sr- sra src srd srr srs ss- ssa ssc ssd ssr sss