cccc cccf ccfc ccff ccoc ccrc ccrf cfcf cfco cffr cfor ckck ckco ckfr ckoc ckoo ckor ckrc cock coco cofc coff cok- coko coof cook cor- corc corf cork coro corr crcc crcr crfc crkc croc crok croo cror f--k fccf ffcc ffff ffrr fock foco fofo foof fook for- fork foro forr frcc frfc kccc kcck kccr kcfc kcfo kckc kckf kckk kcko kckr kcof kcor kcrc kcro kcrr kfcf kfco kfcr kfff kffk kfok kfoo kfor kfrc kfro kfrr kkck kkco kkcr kkfr kkkk kkoo kkor kkrc kkrf kkrk kkro kkrr kocf kock kofc koff kofk kofo kokc kokf kokk koko kokr kooc kook kooo koor korc korf kork koro korr krcc krco krfc krff krfo krkc krkk krko krkr kroc krof krok kroo kror krrc krrf krrk krro krrr occc ocro ocrr ofcr off- offc offo offr ofor okko okok okor okro oocr ooff oooo orco orff orko oro- orof orok oror orro rccc rcfc rffc rkkf rocc rock roco rofc roff rofo rokk roko rokr roof rook roor rorc rork roro rrfc rrrr