-er a-a a-b a-c aaa aab aac aad aae aam aar ab- aba abb abc abd abe abm abr ac- aca acb acc acd ace acm acr ad- ada adb adc add ade adm adr aea aeb aec aed aee aem aer ama amb amc amd ame amm amr ar- ara arb arc ard are arm arr baa bab bac bad bae bam bar bba bbb bbc bbd bbe bbm bbr bca bcb bcc bcd bce bcm bcr bda bdb bdc bdd bde bdm bdr be- bea beb bec bed bee bem ber bma bmb bmc bmd bme bmm bmr bra brb brd bre brm brr c-- caa cab cac cad cae cam car cba cbb cbc cbd cbe cbm cbr cca ccb ccc ccd cce ccm ccr cda cdb cdc cdd cde cdm cdr ce- cea ceb cec ced cee cem cer cma cmb cmc cmd cme cmm cmr cra crb crc crd cre crm crr daa dab dac dad dae dam dar dba dbb dbc dbd dbe dbm dbr dca dcb dcc dcd dce dcm dcr dda ddb ddc ddd dde ddm ddr de- dea deb dec ded dee dem der dma dmb dmc dmd dme dmm dmr dra drb drc drd dre drm drr eaa eab eac ead eae eam ear eba ebb ebc ebd ebe ebm ebr ec- eca ecb ecc ecd ece ecm ecr ed- eda edb edc edd ede edm edr eea eeb eec eed eee eem eer em- ema emb emc emd eme emm emr era erb erc erd ere erm err m-r maa mab mac mad mae mam mar mba mbb mbc mbd mbe mbm mbr mc- mca mcb mcc mcd mce mcm mcr mda mdb mdc mdd mde mdm mdr mea meb mec med mee mem mer mma mmb mmc mmd mme mmm mmr mra mrb mrc mrd mre mrm mrr ra- raa rab rac rad rae ram rar rba rbb rbc rbd rbe rbm rbr rca rcb rcc rcd rce rcm rcr rda rdb rdc rdd rde rdm rdr re- rea reb rec red ree rem rer rma rmb rmc rmd rme rmm rmr rra rrb rrc rrd rrm rrr