bbb bbe bbi bbk bbo bbs be- beb bee bei bek beo bes bi- bib bie bii bik bio bis bkb bke bkk bko bks bob boe boi bok boo bos bsb bse bsi bsk bso bss ebb ebe ebi ebk ebo ebs eeb eee eek eeo ees eib eie eii eik eio eis ekb eke eki eko eks eo- eob eoe eoi eok eoo eos es- esb ese esi esk eso ess ibb ibe ibi ibk ibo ibs ie- iee iei iek ies iib iie iii iio iis ikb ike iki ikk iko iks io- iob ioe ioi ioo ios is- isb ise isi isk iso iss kbb kbe kbi kbk kbo kbs ke- keb kee kei kek keo kes kib kie kii kik kio kis kkb kke kki kkk kks kob koe koi kok koo kos ksb kse ksi ksk kso kss o-i ob- obb obe obi obk obo obs oeb oee oei oeo oes oib oie oii oik oio ois okb oke oki okk oko oks oo- oob ooi ook ooo oos os- osb ose osi osk oso oss sbb sbe sbi sbk sbo sbs se- seb see sei sek seo ses sib sie sii sik sio sis sk- skb ske ski skk sko sks sob soe soi sok soo sos ss- ssb sse ssi ssk sso sss