a-a a-b aaa aab aad aao aap aar aas ab- aba abb abd abo abp abr abs ad- ada adb add ado adp adr ads aoa aob aod aoo aop aor aos ap- apa apb apd apo app apr aps ar- ara arb ard aro arp arr ars as- asa asb asd aso asp asr ass b-p baa bab bad bao bap bar bas bba bbb bbd bbo bbp bbr bbs bda bdb bdd bdo bdp bdr bds boa bob bod boo bop bor bos bpa bpb bpd bpo bpp bpr bps bra brb brd bro brp brr brs bsa bsb bsd bso bsp bsr bss daa dab dad dao dap dar das dba dbb dbd dbo dbp dbr dbs dda ddb ddd ddo ddp ddr dds doa dob dod doo dop dor dos dpa dpb dpd dpo dpp dpr dps dra drb drd dro drp drr drs dsa dsb dsd dso dsp dsr dss oaa oab oad oao oap oar oas ob- oba obb obd obo obp obr obs oda odb odd odo odp odr ods oo- ooa oob ood ooo oop oor oos op- opa opb opd opo opp opr ops or- ora orb ord oro orp orr ors os- osa osb osd oso osp osr oss p-p paa pab pad pao pap par pas pba pbb pbd pbo pbp pbr pbs pda pdb pdd pdo pdp pdr pds poa pob pod poo pop por pos ppa ppb ppd ppo ppp ppr pps pra prb prd pro prp prr prs ps- psa psb psd pso psp psr pss ra- raa rab rad rao rap rar ras rba rbb rbd rbo rbp rbr rbs rda rdb rdd rdo rdp rdr rds roa rob rod roo rop ror ros rpa rpb rpd rpo rpp rpr rps rra rrb rrd rrp rrr rrs rsa rsb rsd rso rsp rsr rss saa sab sad sao sap sar sas sba sbb sbd sbo sbp sbr sbs sda sdb sdd sdo sdp sdr sds soa sob sod soo sop sor sos spa spb spd spo spp spr sps sr- sra srb srd sro srp srr srs ss- ssa ssb ssd sso ssp ssr sss