bbbb bbci bbdd bbdo bcbc bccc bcci bdbc bddc bdii bibb bibi bibo bicc bici bico bidi bido bio- bioc bioi bobb bobi bobo boco bodb bodi bodo boi- boid boii boob booc bood c-bo c-cd cbbc cbcc cbdb cbdc cbdi cbdo cbid ccbc cccb cccc ccci ccdc ccdi ccic ccid ccii ccob ccoc ccod cddb cdic cdii cdio cibc cibi cibo cicc cici cico cidc cidi ciid ciii ciob cobb cobi cobo coco codd codi coob cood d-bo dbcc dcbc dccb dccc dcci dcdb dcii dcio dddd ddoc dibb dibo dici dico didi dido diii dioc dobb dobi doci doco dod- dodd dodi dodo doid doob dood ibdo ibid icbc icbd iccb iccc icci icco icdc icdd icoc icod iddo idic idid idio idoc iicd iiii iiio iioi iioo iobi ioci iod- iodd iodo ioii ioio iooi iooo obbo obid oboi ocbc occc occi odbo odci oddd oddi odic odio odoo oici oido oiii oobi oodi ooid oooo