-er bbb bbc bbe bbm bbr bcb bcc bce bcm bcr bcz be- beb bec bee bem ber bez bmb bmc bme bmm bmr bmz brb bre brm brr brz bze bzr bzz c-- cbb cbc cbe cbm cbr cbz ccb ccc cce ccm ccr ccz ce- ceb cec cee cem cer cez cmb cmc cme cmm cmr crb crc cre crm crr crz cz- czc cze czm ebb ebc ebe ebm ebr ec- ecb ecc ece ecm ecr eeb eec eee eem eer em- emb emc eme emm emr erb erc ere erm err erz eze ezr ezz m-r mbb mbc mbe mbm mbr mc- mcb mcc mce mcm mcr mcz meb mec mee mem mer mez mmb mmc mme mmm mmr mmz mrb mrc mre mrm mrr mrz mzb mzm rbb rbc rbe rbm rbr rcb rcc rce rcm rcr re- reb rec ree rem rer rez rmb rmc rme rmm rmr rrb rrc rrm rrr rzb rze rzm zbb zbc zbm zbr zce zeb zec zee zem zer zez zmb zmc zmm zzr zzz