b-p bbb bbe bbk bbo bbp bbs be- beb bee bek beo bep bes bkb bke bkk bko bkp bks bob boe bok boo bop bos bpb bpe bpo bpp bps bsb bse bsk bso bsp bss ebb ebe ebk ebo ebp ebs eeb eee eek eeo eep ees ekb eke eko ekp eks eo- eob eoe eok eoo eop eos ep- epb epe epo epp eps es- esb ese esk eso esp ess kbb kbe kbk kbo kbp kbs ke- keb kee kek keo kep kes kkb kke kkk kkp kks kob koe kok koo kop kos kpe kpk kpo kpp kps ksb kse ksk kso ksp kss ob- obb obe obk obo obp obs oeb oee oeo oep oes okb oke okk oko okp oks oo- oob ook ooo oop oos op- opb ope opk opo opp ops os- osb ose osk oso osp oss p-p pbb pbe pbk pbo pbp pbs peb pee pek peo pep pes pkb pke pko pkp pks pob poe pok poo pop pos ppb ppe ppk ppo ppp pps ps- psb pse psk pso psp pss sbb sbe sbk sbo sbp sbs se- seb see sek seo sep ses sk- skb ske skk sko skp sks sob soe sok soo sop sos spb spe spk spo spp sps ss- ssb sse ssk sso ssp sss