c-- ccc cce cck cco cct ccz ce- cec cee cek ceo cet cez ckc cko ckt co- coc coe cok coo cot coz ctc cte ctk cto ctt ctz cz- czc cze czk czo czt ec- ecc ece eck eco ect eec eee eek eeo eet ekc eke eko ekt eo- eoc eoe eok eoo eot etc ete etk eto ett etz eze ezo ezz k-t k-z kcc kce kck kct ke- kec kee kek keo ket kez kkc kke kkk kkt koc koe kok koo kot koz ktc kte ktk kto ktt kzo oc- occ ock oco oct ocz oec oee oeo oet okc oke okk oko oo- ooc ook ooo oot ot- otc ote otk oto ott otz oze ozo ozt ozz tcc tce tck tco tct te- tec tee tek teo tet tez tkc tke tkk tko tkt tkz to- toc toe tok too tot toz ttc tte ttk tto ttt tze zce zco zec zee zek zeo zet zez zo- zoc zoe zok zoo zot zte zzt zzz