-er a-a a-b a-c aaa aab aac aae aam aar ab- aba abb abc abe abm abr ac- aca acb acc ace acm acr aea aeb aec aee aem aer ama amb amc ame amm amr ar- ara arb arc are arm arr baa bab bac bae bam bar bba bbb bbc bbe bbm bbr bca bcb bcc bce bcm bcr be- bea beb bec bee bem ber bma bmb bmc bme bmm bmr bra brb bre brm brr c-- caa cab cac cae cam car cba cbb cbc cbe cbm cbr cca ccb ccc cce ccm ccr ce- cea ceb cec cee cem cer cma cmb cmc cme cmm cmr cra crb crc cre crm crr eaa eab eac eae eam ear eba ebb ebc ebe ebm ebr ec- eca ecb ecc ece ecm ecr eea eeb eec eee eem eer em- ema emb emc eme emm emr era erb erc ere erm err m-r maa mab mac mae mam mar mba mbb mbc mbe mbm mbr mc- mca mcb mcc mce mcm mcr mea meb mec mee mem mer mma mmb mmc mme mmm mmr mra mrb mrc mre mrm mrr ra- raa rab rac rae ram rar rba rbb rbc rbe rbm rbr rca rcb rcc rce rcm rcr re- rea reb rec ree rem rer rma rmb rmc rme rmm rmr rra rrb rrc rrm rrr