a-a a-b a-c a-t aaa aab aac aad aak aan aar aas aat ab- aba abb abc abd abk abn abr abs abt ac- aca acb acc acd ack acn acr acs act ad- ada adb adc add adk adn adr ads adt aka akb akc akd akk akn akr aks an- ana anb anc and ank ann anr ans ant ar- ara arb arc ard ark arn arr ars art as- asa asb asc asd ask asn asr ass ast at- ata atb atc atd atn atr ats att baa bab bac bad bak ban bar bas bat bba bbb bbc bbd bbk bbn bbr bbs bbt bca bcb bcc bcd bck bcn bcr bcs bct bda bdb bdc bdd bdk bdr bds bdt bka bkb bkc bkk bkn bkr bks bkt bna bnb bnc bnd bnk bnn bnr bns bnt bra brb brd brk brn brr brs brt bsa bsb bsc bsd bsk bsn bsr bss bst bta btb btc btd btk btn btr bts btt c-- caa cab cac cad cak can car cas cat cba cbb cbc cbd cbk cbn cbr cbs cbt cca ccb ccc ccd cck ccn ccr ccs cct cda cdb cdc cdd cdk cdn cdr cds cdt cka ckb ckc ckd cks ckt cn- cna cnb cnc cnd cnn cnr cns cnt cra crb crc crd crk crn crr crs crt csa csb csc csd csk csn csr css cst cta ctb ctc ctd ctk ctn ctr cts ctt daa dab dac dad dak dan dar das dat dba dbb dbc dbd dbk dbn dbr dbs dbt dca dcb dcc dcd dck dcn dcr dcs dct dda ddb ddc ddd ddk ddn ddr dds ddt dka dkb dkc dkk dkr dks dkt dna dnb dnc dnd dnk dnn dnr dns dnt dra drb drc drd drk drn drr drs drt dsa dsb dsc dsd dsk dsn dsr dss dst dta dtb dtc dtd dtk dtn dtr dts dtt k-t ka- kaa kab kac kad kak kan kar kas kat kba kbb kbc kbd kbk kbn kbr kbs kca kcb kcc kcd kck kcn kcr kcs kct kda kdb kdc kdk kdr kds kdt kkb kkc kkk kkn kkr kks kkt kn- kna knc knd knk knn knr knt kra krc krd krk krn krr krs krt ksa ksb ksc ksd ksk ksn ksr kss kst kta ktb ktc ktk ktn ktr kts ktt naa nab nac nad nak nan nar nas nat nba nbb nbc nbd nbk nbn nbr nbs nbt nca ncb ncc ncd nck ncn ncr ncs nct nda ndb ndc ndd ndk ndn ndr nds ndt nka nkc nkk nkn nkr nks nkt nna nnb nnc nnk nnn nns nnt nra nrb nrc nrd nrk nrn nrr nrs nrt nsa nsb nsc nsd nsk nsn nsr nss nst nta ntb ntc ntd ntk ntn ntr nts ntt ra- raa rab rac rad rak ran rar ras rat rba rbb rbc rbd rbk rbn rbr rbs rbt rca rcb rcc rcd rcn rcr rcs rct rda rdb rdc rdd rdn rdr rds rdt rkb rkc rkk rks rkt rna rnb rnc rnd rnn rnr rns rnt rra rrb rrc rrd rrk rrn rrr rrs rrt rsa rsb rsc rsd rsk rsn rsr rss rst rta rtb rtc rtd rtk rtn rtr rts rtt saa sab sac sad sak san sar sas sat sba sbb sbc sbd sbk sbn sbr sbs sbt sca scb scc scd sck scn scr scs sct sda sdb sdc sdd sdk sdn sdr sds sdt sk- ska skb skc skd skk skr sks skt sna snb snc snd snk snn snr sns snt sr- sra srb src srd srk srn srr srs srt ss- ssa ssb ssc ssd ssk ssn ssr sss sst sta stb stc std stk stn str sts stt taa tab tac tad tak tan tar tas tat tba tbb tbc tbd tbk tbn tbr tbs tbt tca tcb tcc tcd tck tcn tcr tcs tct tda tdb tdc tdd tdk tdn tdr tds tdt tka tkb tkc tkk tkr tks tkt tna tnb tnc tnd tnk tnn tnr tns tnt tra trb trc trd trk trn trr trs trt tsa tsb tsc tsd tsk tsn tsr tss tst tta ttb ttc ttd ttk ttn ttr tts ttt