a-a a-b a-c aaa aab aac aad aan aar aas ab- aba abb abc abd abn abr abs ac- aca acb acc acd acn acr acs ad- ada adb adc add adn adr ads an- ana anb anc and ann anr ans ar- ara arb arc ard arn arr ars as- asa asb asc asd asn asr ass baa bab bac bad ban bar bas bba bbb bbc bbd bbn bbr bbs bca bcb bcc bcd bcn bcr bcs bda bdb bdc bdd bdr bds bna bnb bnc bnd bnn bnr bns bra brb brd brn brr brs bsa bsb bsc bsd bsn bsr bss c-- caa cab cac cad can car cas cba cbb cbc cbd cbn cbr cbs cca ccb ccc ccd ccn ccr ccs cda cdb cdc cdd cdn cdr cds cn- cna cnb cnc cnd cnn cnr cns cra crb crc crd crn crr crs csa csb csc csd csn csr css daa dab dac dad dan dar das dba dbb dbc dbd dbn dbr dbs dca dcb dcc dcd dcn dcr dcs dda ddb ddc ddd ddn ddr dds dna dnb dnc dnd dnn dnr dns dra drb drc drd drn drr drs dsa dsb dsc dsd dsn dsr dss naa nab nac nad nan nar nas nba nbb nbc nbd nbn nbr nbs nca ncb ncc ncd ncn ncr ncs nda ndb ndc ndd ndn ndr nds nna nnb nnc nnn nns nra nrb nrc nrd nrn nrr nrs nsa nsb nsc nsd nsn nsr nss ra- raa rab rac rad ran rar ras rba rbb rbc rbd rbn rbr rbs rca rcb rcc rcd rcn rcr rcs rda rdb rdc rdd rdn rdr rds rna rnb rnc rnd rnn rnr rns rra rrb rrc rrd rrn rrr rrs rsa rsb rsc rsd rsn rsr rss saa sab sac sad san sar sas sba sbb sbc sbd sbn sbr sbs sca scb scc scd scn scr scs sda sdb sdc sdd sdn sdr sds sna snb snc snd snn snr sns sr- sra srb src srd srn srr srs ss- ssa ssb ssc ssd ssn ssr sss