bbb bbc bbd bbk bbo bbr bbs bbt bcb bcc bcd bck bco bcr bcs bct bdb bdc bdd bdk bdo bdr bds bdt bkb bkc bkk bko bkr bks bkt bob boc bod bok boo bor bos bot brb brd brk bro brr brs brt bsb bsc bsd bsk bso bsr bss bst btb btc btd btk bto btr bts btt c-- cbb cbc cbd cbk cbo cbr cbs cbt ccb ccc ccd cck cco ccr ccs cct cdb cdc cdd cdk cdo cdr cds cdt ckb ckc ckd cko cks ckt co- cob coc cod cok coo cor cos cot crb crc crd crk cro crr crs crt csb csc csd csk cso csr css cst ctb ctc ctd ctk cto ctr cts ctt dbb dbc dbd dbk dbo dbr dbs dbt dcb dcc dcd dck dco dcr dcs dct ddb ddc ddd ddk ddo ddr dds ddt dkb dkc dkk dko dkr dks dkt dob doc dod dok doo dor dos dot drb drc drd drk dro drr drs drt dsb dsc dsd dsk dso dsr dss dst dtb dtc dtd dtk dto dtr dts dtt k-t kbb kbc kbd kbk kbo kbr kbs kcb kcc kcd kck kcr kcs kct kdb kdc kdk kdo kdr kds kdt kkb kkc kkk kkr kks kkt kob koc kod kok koo kor kos kot krc krd krk kro krr krs krt ksb ksc ksd ksk kso ksr kss kst ktb ktc ktk kto ktr kts ktt ob- obb obc obd obk obo obr obs obt oc- ocb occ ocd ock oco ocr ocs oct odb odc odd odo odr ods odt okb okc okd okk oko okr oks oo- oob ooc ood ook ooo oor oos oot or- orb orc ord ork oro orr ors ort os- osb osc osd osk oso osr oss ost ot- otb otc otd otk oto otr ots ott rbb rbc rbd rbk rbo rbr rbs rbt rcb rcc rcd rco rcr rcs rct rdb rdc rdd rdo rdr rds rdt rkb rkc rkk rko rks rkt rob roc rod rok roo ror ros rot rrb rrc rrd rrk rrr rrs rrt rsb rsc rsd rsk rso rsr rss rst rtb rtc rtd rtk rto rtr rts rtt sbb sbc sbd sbk sbo sbr sbs sbt scb scc scd sck sco scr scs sct sdb sdc sdd sdk sdo sdr sds sdt sk- skb skc skd skk sko skr sks skt sob soc sod sok soo sor sos sot sr- srb src srd srk sro srr srs srt ss- ssb ssc ssd ssk sso ssr sss sst stb stc std stk sto str sts stt tbb tbc tbd tbk tbo tbr tbs tbt tcb tcc tcd tck tco tcr tcs tct tdb tdc tdd tdk tdo tdr tds tdt tkb tkc tkk tko tkr tks tkt to- tob toc tod tok too tor tos tot trb trc trd trk tro trr trs trt tsb tsc tsd tsk tso tsr tss tst ttb ttc ttd ttk tto ttr tts ttt