c-- ccc ccf cck cco ccw cfc cff cfk cfo cfw ckc cko ckw cky co- coc cof cok coo cow coy cw- cwc cwk cwo cyc cyf cyk cyo cyw fcc fcf fck fco fcw fcy ffc fff ffk ffo ffw ffy fkc fkf fkk foc fof fok foo fow foy fwc fwf fwo fy- fyc fyk fyo kcc kck kfc kff kfo kfw kkc kkk kky koc kof kok koo kow koy kw- kwc kwf kwk kwo kww kyc kyo kyw oc- occ ocf ock oco ocw of- ofc off ofo ofw okc okk oko okw oo- ooc oof ook ooo oow owc owf owk owo oww oyo wcc wcf wck wco wcw wfc wff wfk wfo wfw wkc wkf wko wkw wky woc wof wok woo wow woy wwc wwf wwo www wy- wyc wyf wyk wyo ycc ycf yco ycw ycy yfc yff ykk yoc yof yok yoo yow yoy ywc yyc yyf yyy