a-a a-c aaa aac aad aao aap aax ac- aca acc acd aco acp acx ad- ada adc add ado adp adx aoa aoc aod aoo aop aox ap- apa apc apd apo app apx ax- axa axo axp axx c-- caa cac cad cao cap cax cca ccc ccd cco ccp ccx cda cdc cdd cdo cdp cdx co- coa coc cod coo cop cox cpa cpc cpd cpo cpp cpx cxc cxo cxp cxx daa dac dad dao dap dax dca dcc dcd dco dcp dcx dda ddc ddd ddo ddp ddx doa doc dod doo dop dox dpa dpc dpd dpo dpp dxc dxd dxo dxp dxx oaa oac oad oao oap oax oc- oca occ ocd oco ocp ocx oda odc odd odo odp oo- ooa ooc ood ooo oop oox op- opa opc opd opo opp opx ox- oxa oxc oxo oxx p-p paa pac pad pao pap pax pca pcc pcd pco pcp pcx pda pdc pdd pdo pdp pdx poa poc pod poo pop pox ppa ppc ppd ppo ppp ppx pxc xaa xac xad xap xcd xcp xcx xda xdc xoa xoc xod xoo xop xox xpa xpc xpd xpo xpp xxo xxp xxx