c-- ccc cco ccp ccx co- coc coo cop cox coy cpc cpo cpp cpx cxc cxo cxp cxx cyc cyo cyp oc- occ oco ocp ocx oo- ooc ooo oop oox op- opc opo opp opx opy ox- oxc oxo oxx oxy oyo p-p pcc pco pcp pcx poc poo pop pox poy ppc ppo ppp ppx pxc py- pyc pyo pyx xcp xcx xoc xoo xop xox xpc xpo xpp xxo xxp xxx xxy xyp xyy ycc yco ycp ycy yoc yoo yop yox yoy ypo yxy yyc yyy