a-a a-c aaa aac aah aao aap ac- aca acc ach aco acp aha ahc ahh aho ahp aoa aoc aoh aoo aop ap- apa apc aph apo app c-- caa cac cah cao cap cca ccc cch cco ccp ch- cha chc chh cho chp co- coa coc coh coo cop cpa cpc cph cpo cpp haa hac hah hao hap hca hcc hch hco hcp hha hhc hhh hho hhp hoa hoc hoh hoo hop hpa hpc hph hpo hpp oaa oac oah oao oap oc- oca occ och oco ocp oha ohc ohh oho ohp oo- ooa ooc ooh ooo oop op- opa opc oph opo opp p-p paa pac pah pao pap pca pcc pch pco pcp pha phc pho php poa poc poh poo pop ppa ppc pph ppo ppp