b-u bbb bbc bbd bbs bbt bbu bcb bcc bcd bcs bct bcu bdb bdc bdd bds bdt bdu bsb bsc bsd bss bst bsu btb btc btd bts btt btu bub buc bud bus but buu c-- cbb cbc cbd cbs cbt cbu ccb ccc ccd ccs cct ccu cdb cdc cdd cds cdt cdu csb csc csd css cst csu ctb ctc ctd cts ctt ctu cub cuc cud cus cut cuu dbb dbc dbd dbs dbt dbu dcb dcc dcd dcs dct dcu ddb ddc ddd dds ddt ddu dsb dsc dsd dss dst dsu dtb dtc dtd dts dtt dtu dub duc dud dus dut sbb sbc sbd sbs sbt sbu scb scc scd scs sct scu sdb sdc sdd sds sdt sdu ss- ssb ssc ssd sss sst ssu stb stc std sts stt stu sub suc sud sus sut suu tbb tbc tbd tbs tbt tbu tcb tcc tcd tcs tct tcu tdb tdc tdd tds tdt tdu tsb tsc tsd tss tst tsu ttb ttc ttd tts ttt ttu tub tuc tud tus tut tuu ubb ubc ubs ubt ubu ucb ucc ucd ucs uct ucu udb udc udd uds udt udu usb usc usd uss ust usu utb utc utd uts utt utu uuc uus uut uuu