a-a a-b a-c a-t aaa aab aac aae aam aas aat ab- aba abb abc abe abm abs abt ac- aca acb acc ace acm acs act aea aeb aec aee aem aes aet ama amb amc ame amm ams amt as- asa asb asc ase asm ass ast at- ata atb atc ate atm ats att baa bab bac bae bam bas bat bba bbb bbc bbe bbm bbs bbt bca bcb bcc bce bcm bcs bct be- bea beb bec bee bem bes bet bma bmb bmc bme bmm bms bmt bsa bsb bsc bse bsm bss bst bta btb btc bte btm bts btt c-- caa cab cac cae cam cas cat cba cbb cbc cbe cbm cbs cbt cca ccb ccc cce ccm ccs cct ce- cea ceb cec cee cem ces cet cma cmb cmc cme cmm cms cmt csa csb csc cse csm css cst cta ctb ctc cte ctm cts ctt eaa eab eac eae eam eas eat eba ebb ebc ebe ebm ebs ebt ec- eca ecb ecc ece ecm ecs ect eea eeb eec eee eem ees eet em- ema emb emc eme emm ems emt es- esa esb esc ese esm ess est eta etb etc ete etm ets ett maa mab mac mae mam mas mat mba mbb mbc mbe mbm mbs mbt mc- mca mcb mcc mce mcm mcs mct mea meb mec mee mem mes met mma mmb mmc mme mmm mms mmt msa msb msc mse msm mss mst mta mtb mtc mte mtm mts mtt saa sab sac sae sam sas sat sba sbb sbc sbe sbm sbs sbt sca scb scc sce scm scs sct se- sea seb sec see sem ses set sma smb smc sme smm sms smt ss- ssa ssb ssc sse ssm sss sst sta stb stc ste stm sts stt taa tab tac tae tam tas tat tba tbb tbc tbe tbm tbs tbt tca tcb tcc tce tcm tcs tct te- tea teb tec tee tem tes tet tma tmb tmc tme tmm tms tmt tsa tsb tsc tse tsm tss tst tta ttb ttc tte ttm tts ttt