a-a aaa aad aao aap aar aax ad- ada add ado adp adr adx aoa aod aoo aop aor aox ap- apa apd apo app apr apx ar- ara ard aro arp arr arx ax- axa axo axp axr axx daa dad dao dap dar dax dda ddd ddo ddp ddr ddx doa dod doo dop dor dox dpa dpd dpo dpp dpr dra drd dro drp drr drx dxd dxo dxp dxr dxx oaa oad oao oap oar oax oda odd odo odp odr oo- ooa ood ooo oop oor oox op- opa opd opo opp opr opx or- ora ord oro orp orr orx ox- oxa oxo oxx p-p paa pad pao pap par pax pda pdd pdo pdp pdr pdx poa pod poo pop por pox ppa ppd ppo ppp ppr ppx pra prd pro prp prr prx pxr ra- raa rad rao rap rar rax rda rdd rdo rdp rdr rdx roa rod roo rop ror rox rpa rpd rpo rpp rpr rpx rra rrd rrp rrr rxp rxr xaa xad xap xar xda xdr xoa xod xoo xop xor xox xpa xpd xpo xpp xrd xrx xxo xxp xxx