a-a a-b aaa aab aad aae aag aao ab- aba abb abd abe abg abo ad- ada adb add ade adg ado aea aeb aed aee aeg aeo ag- aga agb agd age agg ago aoa aob aod aoe aog aoo baa bab bad bae bag bao bba bbb bbd bbe bbg bbo bda bdb bdd bde bdg bdo be- bea beb bed bee beg beo bga bgb bgd bge bgg bgo boa bob bod boe bog boo daa dab dad dae dag dao dba dbb dbd dbe dbg dbo dda ddb ddd dde ddg ddo de- dea deb ded dee deg deo dga dgd dge dgg doa dob dod doe dog doo eaa eab ead eae eag eao eba ebb ebd ebe ebg ebo ed- eda edb edd ede edg edo eea eeb eed eee eeg eeo ega egb egd ege egg ego eo- eoa eob eod eoe eog eoo g-d gaa gab gad gae gag gao gba gbd gbe gbg gbo gda gdb gdd gde gdo ge- gea geb ged gee geg geo gga ggb ggd ggg ggo goa gob god goe gog goo oaa oab oad oae oag oao ob- oba obb obd obe obg obo oda odb odd ode odg odo oea oeb oed oee oeg oeo oga ogd oge ogg ogo oo- ooa oob ood oog ooo