c-- ccc cch cco ccp ch- chc chh cho chp chy co- coc coh coo cop coy cpc cph cpo cpp cyc cyo cyp hcc hch hco hcp hcy hhc hhh hho hhp hhy hoc hoh hoo hop hoy hpc hph hpo hpp hpy hy- hyc hyh hyo hyp hyy oc- occ och oco ocp ohc ohh oho ohp oo- ooc ooh ooo oop op- opc oph opo opp opy oyo p-p pcc pch pco pcp phc pho php phy poc poh poo pop poy ppc pph ppo ppp py- pyc pyo ycc ych yco ycp ycy yhc yoc yoo yop yoy ypo yyc yyy