a-a aaa aad aao aap aar ad- ada add ado adp adr aoa aod aoo aop aor ap- apa apd apo app apr ar- ara ard aro arp arr daa dad dao dap dar dda ddd ddo ddp ddr doa dod doo dop dor dpa dpd dpo dpp dpr dra drd dro drp drr oaa oad oao oap oar oda odd odo odp odr oo- ooa ood ooo oop oor op- opa opd opo opp opr or- ora ord oro orp orr p-p paa pad pao pap par pda pdd pdo pdp pdr poa pod poo pop por ppa ppd ppo ppp ppr pra prd pro prp prr ra- raa rad rao rap rar rda rdd rdo rdp rdr roa rod roo rop ror rpa rpd rpo rpp rpr rra rrd rrp rrr