-ol bbb bbc bbe bbl bbo bcb bcc bce bcl bco be- beb bec bee bel beo blb blc ble bll blo bob boc boe bol boo c-- cbb cbc cbe cbl cbo ccb ccc cce ccl cco ce- ceb cec cee cel ceo cl- clb clc cle cll clo co- cob coc coe col coo ebb ebc ebe ebl ebo ec- ecb ecc ece ecl eco eeb eec eee eel eeo elb elc ele ell elo eo- eob eoc eoe eol eoo lbb lbc lbe lbl lbo lcb lcc lce lcl lco leb lec lee lel leo llb llc lle lll llo lob loc loe lol loo ob- obb obc obe obl obo oc- ocb occ ocl oco oeb oec oee oel oeo olb olc ole oll olo oo- oob ooc ool ooo