bbbb bbci bcbc bccc bcci bcit bctc bcuc bibb bibi bicc bici bitc bitt bitu btcc bttb bubb bubi bubu bucc buci bucu buic buit buiu but- buti butt cbbc cbcc cbct cbcu cbit cbtc ccbc cccb cccc ccci cccu ccic ccii cctb cctc cctt ccuc ccut cibc cibi cicc cici cict cicu ciii ciit citb citi citt citu ciuc ctbi ctic cub- cubb cubi cucc cuci cui- cuit cut- cutc cutt ibtb ibtc icbc iccb iccc icci icct iccu icub iiii iiit iitt iiuc itic iucc iuiu tbcb tbcc tbit tccc tccu tctc tibi tibu ticc tiit tiiu titc titi titt titu ttbb tttt tubb tubu tucc tuit tuiu tuti tutt tutu ubbi ubic ubii ubit ucbc ucci ucut utti uttu uuuu