a-a a-b a-c aaa aab aac aad aae aak aam aao ab- aba abb abc abd abe abk abm abo ac- aca acb acc acd ace ack acm aco ad- ada adb adc add ade adk adm ado aea aeb aec aed aee aek aem aeo aka akb akc akd ake akk akm ako ama amb amc amd ame amk amm amo aoa aob aoc aod aoe aok aom aoo baa bab bac bad bae bak bam bao bba bbb bbc bbd bbe bbk bbm bbo bca bcb bcc bcd bce bck bcm bco bda bdb bdc bdd bde bdk bdm bdo be- bea beb bec bed bee bek bem beo bka bkb bkc bke bkk bkm bko bma bmb bmc bmd bme bmk bmm bmo boa bob boc bod boe bok bom boo c-- caa cab cac cad cae cak cam cao cba cbb cbc cbd cbe cbk cbm cbo cca ccb ccc ccd cce cck ccm cco cda cdb cdc cdd cde cdk cdm cdo ce- cea ceb cec ced cee cek cem ceo cka ckb ckc ckd ckm cko cma cmb cmc cmd cme cmk cmm cmo co- coa cob coc cod coe cok com coo daa dab dac dad dae dak dam dao dba dbb dbc dbd dbe dbk dbm dbo dca dcb dcc dcd dce dck dcm dco dda ddb ddc ddd dde ddk ddm ddo de- dea deb dec ded dee dek dem deo dka dkb dkc dke dkk dkm dko dma dmb dmc dmd dme dmk dmm dmo doa dob doc dod doe dok dom doo eaa eab eac ead eae eak eam eao eba ebb ebc ebd ebe ebk ebm ebo ec- eca ecb ecc ecd ece eck ecm eco ed- eda edb edc edd ede edk edm edo eea eeb eec eed eee eek eem eeo eka ekb ekc ekd eke eko em- ema emb emc emd eme emk emm emo eo- eoa eob eoc eod eoe eok eom eoo ka- kaa kab kac kad kae kak kam kao kba kbb kbc kbd kbe kbk kbm kbo kca kcb kcc kcd kce kck kcm kda kdb kdc kde kdk kdm kdo ke- kea keb kec ked kee kek kem keo kkb kkc kke kkk kkm kma kmb kmc kmd kme kmk kmm kmo koa kob koc kod koe kok kom koo m-o maa mab mac mad mae mak mam mao mba mbb mbc mbd mbe mbk mbm mbo mc- mca mcb mcc mcd mce mck mcm mco mda mdb mdc mdd mde mdk mdm mdo mea meb mec med mee mek mem meo mka mkb mkc mkd mke mkk mkm mko mma mmb mmc mmd mme mmk mmm mmo moa mob moc mod moe mok mom moo oaa oab oac oad oae oak oam oao ob- oba obb obc obd obe obk obm obo oc- oca ocb occ ocd ock ocm oco oda odb odc odd ode odm odo oea oeb oec oed oee oem oeo oka okb okc okd oke okk oko om- oma omb omc omd ome omm omo oo- ooa oob ooc ood ook oom ooo