bbb bbc bbs bbt bcb bcc bcs bct bcv bsb bsc bss bst bsv btb btc bts btt btv bvb bvc bvs bvt bvv c-- cbb cbc cbs cbt cbv ccb ccc ccs cct ccv csb csc css cst csv ctb ctc cts ctt ctv cvb cvc cvs cvt cvv sbb sbc sbs sbt sbv scb scc scs sct scv ss- ssb ssc sss sst ssv stb stc sts stt stv svb svc svs svt svv tbb tbc tbs tbt tbv tcb tcc tcs tct tcv tsb tsc tss tst tsv ttb ttc tts ttt ttv tvb tvc tvs tvt vbc vbs vbv vcc vcs vct vsb vsc vss vst vsv vtb vtc vts vtt vtv vvb vvc vvs vvt vvv