-ol bbb bbc bbd bbe bbk bbl bbo bcb bcc bcd bce bck bcl bco bdb bdc bdd bde bdk bdl bdo be- beb bec bed bee bek bel beo bkb bkc bke bkk bkl bko blb blc bld ble blk bll blo bob boc bod boe bok bol boo c-- cbb cbc cbd cbe cbk cbl cbo ccb ccc ccd cce cck ccl cco cdb cdc cdd cde cdk cdl cdo ce- ceb cec ced cee cek cel ceo ckb ckc ckd cko cl- clb clc cld cle clk cll clo co- cob coc cod coe cok col coo dbb dbc dbd dbe dbk dbl dbo dcb dcc dcd dce dck dcl dco ddb ddc ddd dde ddk ddl ddo de- deb dec ded dee dek del deo dkb dkc dke dkk dkl dko dl- dlb dlc dld dle dlk dll dlo dob doc dod doe dok dol doo ebb ebc ebd ebe ebk ebl ebo ec- ecb ecc ecd ece eck ecl eco ed- edb edc edd ede edk edl edo eeb eec eed eee eek eel eeo ekb ekc ekd eke ekl eko elb elc eld ele elk ell elo eo- eob eoc eod eoe eok eol eoo kbb kbc kbd kbe kbk kbl kbo kcb kcc kcd kce kck kcl kdb kdc kde kdk kdl kdo ke- keb kec ked kee kek kel keo kkb kkc kke kkk kkl kl- klb klc kld klo kob koc kod koe kok kol koo lbb lbc lbd lbe lbk lbl lbo lcb lcc lcd lce lck lcl lco ldb ldc ldd lde ldk ldl ldo leb lec led lee lek lel leo lkb lkl llb llc lld lle llk lll llo lob loc lod loe lok lol loo ob- obb obc obd obe obk obl obo oc- ocb occ ocd ock ocl oco odb odc odd ode odl odo oeb oec oed oee oel oeo okb okc okd oke okk okl oko olb olc old ole olk oll olo oo- oob ooc ood ook ool ooo