-ol bbb bbc bbh bbk bbl bbo bbs bcb bcc bch bck bcl bco bcs bhb bhc bhh bhk bhl bho bhs bkb bkc bkk bkl bko bks blb blc blh blk bll blo bls bob boc boh bok bol boo bos bsb bsc bsh bsk bsl bso bss c-- cbb cbc cbh cbk cbl cbo cbs ccb ccc cch cck ccl cco ccs ch- chb chc chh chk chl cho chs ckb ckc ckh cko cks cl- clb clc clh clk cll clo cls co- cob coc coh cok col coo cos csb csc csh csk csl cso css hbb hbc hbh hbk hbl hbo hbs hcb hcc hch hck hcl hco hcs hhb hhc hhh hhk hhl hho hhs hkb hkh hkk hkl hko hks hlb hlc hlh hll hlo hls hob hoc hoh hok hol hoo hos hsb hsc hsh hsk hsl hss kbb kbc kbh kbk kbl kbo kbs kcb kcc kch kck kcl kcs khh khk kho khs kkb kkc kkh kkk kkl kks kl- klb klc klh klo kls kob koc koh kok kol koo kos ksb ksc ksh ksk ksl kso kss lbb lbc lbh lbk lbl lbo lbs lcb lcc lch lck lcl lco lcs lhb lhc lhh lhk lho lhs lkb lkh lkl lks llb llc llk lll llo lls lob loc loh lok lol loo los lsb lsc lsh lsk lsl lso lss ob- obb obc obh obk obl obo obs oc- ocb occ och ock ocl oco ocs ohc ohh ohl oho ohs okb okc okk okl oko oks olb olc olk oll olo ols oo- oob ooc ooh ook ool ooo oos os- osb osc osh osk osl oso oss sbb sbc sbh sbk sbl sbo sbs scb scc sch sck scl sco scs sh- shb shc shh shk shl sho shs sk- skb skc skh skk skl sko sks slb slc slh slk sll slo sls sob soc soh sok sol soo sos ss- ssb ssc ssh ssk ssl sso sss