a-a a-c aaa aac aad aae aao aax ac- aca acc acd ace aco acx ad- ada adc add ade ado adx aea aec aed aee aeo aex aoa aoc aod aoe aoo aox ax- axa axe axo axx c-- caa cac cad cae cao cax cca ccc ccd cce cco ccx cda cdc cdd cde cdo cdx ce- cea cec ced cee ceo cex co- coa coc cod coe coo cox cxc cxo cxx daa dac dad dae dao dax dca dcc dcd dce dco dcx dda ddc ddd dde ddo ddx de- dea dec ded dee deo dex doa doc dod doe doo dox dxc dxd dxo dxx eaa eac ead eae eao eax ec- eca ecc ecd ece eco ecx ed- eda edc edd ede edo edx eea eec eed eee eeo eex eo- eoa eoc eod eoe eoo ex- exa exc exd exe exo exx oaa oac oad oae oao oax oc- oca occ ocd oco ocx oda odc odd ode odo oea oec oed oee oeo oex oo- ooa ooc ood ooo oox ox- oxa oxc oxo oxx xaa xac xad xcd xcx xda xdc xde xed xee xex xoa xoc xod xoo xox xxo xxx