a-a a-b a-t aaa aab aad aae aao aat aax ab- aba abb abd abe abo abt abx ad- ada adb add ade ado adt adx aea aeb aed aee aeo aet aex aoa aob aod aoe aoo aot aox at- ata atb atd ate ato att atx ax- axa axe axo axt axx baa bab bad bae bao bat bax bba bbb bbd bbe bbo bbt bbx bda bdb bdd bde bdo bdt bdx be- bea beb bed bee beo bet bex boa bob bod boe boo bot box bta btb btd bte bto btt btx bxb bxd bxo bxx daa dab dad dae dao dat dax dba dbb dbd dbe dbo dbt dbx dda ddb ddd dde ddo ddt ddx de- dea deb ded dee deo det dex doa dob dod doe doo dot dox dta dtb dtd dte dto dtt dtx dxd dxo dxt dxx eaa eab ead eae eao eat eax eba ebb ebd ebe ebo ebt ebx ed- eda edb edd ede edo edt edx eea eeb eed eee eeo eet eex eo- eoa eob eod eoe eoo eot eta etb etd ete eto ett etx ex- exa exd exe exo ext exx oaa oab oad oae oao oat oax ob- oba obb obd obe obo obt obx oda odb odd ode odo odt oea oeb oed oee oeo oet oex oo- ooa oob ood ooo oot oox ot- ota otb otd ote oto ott ox- oxa oxb oxo oxt oxx t-x taa tab tad tae tao tat tax tba tbb tbd tbe tbo tbt tda tdb tdd tde tdo tdt tdx te- tea teb ted tee teo tet tex to- toa tob tod toe too tot tox tta ttb ttd tte tto ttt ttx txe txt xaa xad xat xbe xbx xda xdb xde xdt xed xee xet xex xoa xod xoo xot xox xtx xxo xxx