c-- ccc cck cco ccr ccw ckc cko ckw co- coc cok coo cor cow crc crk cro crr crw cw- cwc cwk cwo cwr kcc kck kcr kkc kkk kkr koc kok koo kor kow krc krk kro krr krw kw- kwc kwk kwo kww oc- occ ock oco ocr ocw okc okk oko okr okw oo- ooc ook ooo oor oow or- orc ork oro orr owc owk owo oww rcc rco rcr rcw rkc rkk rko roc rok roo ror row rrc rrk rrr rwc rwr wcc wck wco wcr wcw wkc wko wkr wkw woc wok woo wor wow wr- wrc wrk wro wrr wrw wwc wwo www