bbbb bbbq bbrc bcbc bccc bcor bcru bcuc bobb bobo bobu boco bocq bocu boob booc boor bor- boro borr boru bour brcb brob broc broo bror brou brrr bruc bubb bubo bubq bubu bucc buco bucu bur- burb buro burr buru c-bo cbbc cbcc cbcr cbcu cboq ccbc cccb cccc cccu ccob ccoc ccrc ccuc cobb cobo cobu coco cocu coob cor- corb corc coro corr coub cour crbc crbu crcc crcr crob croc croo cror crub cub- cubb cucc cucq curb curo curr obbo oboq obor obro ocbc occc ocro ocrr ocur oocr oooo orbb orbo orbu orco oro- oror orro orub oucc our- ouro ouu- qobu qoob qqqq qubo qucu quob quoc quor quro quu- rbbb rbbr rcbc rcbo rccb rccc rob- robb robo robu rocc roco roob roor rorc roro roru roub rrrr rubb rubu rurc ruro ruru ubbo uboc ucbc ucrc uocc uor- uqcc uro- uroo uruq urur uuoc uuuu