a-a a-c aaa aac aad aae aaf aao ac- aca acc acd ace acf aco ad- ada adc add ade adf ado aea aec aed aee aef aeo af- afa afc afd afe aff afo aoa aoc aod aoe aof aoo c-- caa cac cad cae caf cao cca ccc ccd cce ccf cco cda cdc cdd cde cdf cdo ce- cea cec ced cee cef ceo cfa cfc cfd cfe cff cfo co- coa coc cod coe cof coo daa dac dad dae daf dao dca dcc dcd dce dcf dco dda ddc ddd dde ddf ddo de- dea dec ded dee def deo dfa dfc dfd dfe dff dfo doa doc dod doe dof doo eaa eac ead eae eaf eao ec- eca ecc ecd ece ecf eco ed- eda edc edd ede edf edo eea eec eed eee eef eeo ef- efa efc efd efe eff efo eo- eoa eoc eod eoe eof eoo faa fac fad fae faf fao fca fcc fcd fce fcf fco fda fdc fdd fde fdf fdo fea fec fed fee fef feo ffa ffc ffd ffe fff ffo foa foc foe fof foo oaa oac oad oae oaf oao oc- oca occ ocd ocf oco oda odc odd ode odf odo oea oec oed oee oef oeo of- ofa ofc ofd ofe off ofo oo- ooa ooc ood oof ooo