bbbb bbch bbrc bcbc bccc bcor bhcc bhor bobb bobo boch boco boho bohr boob booc booh boor bor- borh boro borr brcb brob broc broh broo bror brrr c-bo cbbc cbcc cbcr cbrh ccbc cccb cccc cchr ccob ccoc ccrc chch choc choh choo chor chrb chrc chro chrr cobb cobh cobo coch coco coho coob cooh cor- corb corc coro corr crbc crcc crcr crob croc croh croo cror hboc hcbc hccb hccc hcch hhhh hobo hoch hocr hoho hoor horc horo horr hrob hrrc obbo obor obrh obro ocbc occc ocro ocrr ohcc ohho ohob ohoh oocr ooho oooh oooo orbb orbo orch orco oro- oror orro rbbb rbbr rboh rcbc rcbo rccb rccc rchb rhob rhoc rhoh rob- robb robo rocc roch roco rohr roob roor rorc roro rrrr