-ic bbb bbc bbe bbi bbk bbs bcb bcc bce bci bck bcs be- beb bec bee bei bek bes bi- bib bic bie bii bik bis bkb bkc bke bkk bks bsb bsc bse bsi bsk bss c-- cbb cbc cbe cbi cbk cbs ccb ccc cce cci cck ccs ce- ceb cec cee cei cek ces ci- cib cic cie cii cik cis ckb ckc cki cks csb csc cse csi csk css ebb ebc ebe ebi ebk ebs ec- ecb ecc ece eci eck ecs eeb eec eee eek ees eib eic eie eii eik eis ekb ekc eke eki eks es- esb esc ese esi esk ess ibb ibc ibe ibi ibk ibs icb icc ice ici ick ics ie- iec iee iei iek ies iib iic iie iii iis ikb ikc ike iki ikk iks is- isb isc ise isi isk iss kbb kbc kbe kbi kbk kbs kcb kcc kce kci kck kcs ke- keb kec kee kei kek kes kib kic kie kii kik kis kkb kkc kke kki kkk kks ksb ksc kse ksi ksk kss sbb sbc sbe sbi sbk sbs scb scc sce sci sck scs se- seb sec see sei sek ses sib sic sie sii sik sis sk- skb skc ske ski skk sks ss- ssb ssc sse ssi ssk sss