-er a-a a-b aaa aab aad aae aah aak aao aar ab- aba abb abd abe abh abk abo abr ad- ada adb add ade adh adk ado adr aea aeb aed aee aeh aek aeo aer aha ahb ahd ahe ahh ahk aho ahr aka akb akd ake akh akk ako akr aoa aob aod aoe aoh aok aoo aor ar- ara arb ard are arh ark aro arr baa bab bad bae bah bak bao bar bba bbb bbd bbe bbh bbk bbo bbr bda bdb bdd bde bdh bdk bdo bdr be- bea beb bed bee beh bek beo ber bha bhb bhd bhe bhh bhk bho bhr bka bkb bke bkk bko bkr boa bob bod boe boh bok boo bor bra brb brd bre brh brk bro brr daa dab dad dae dah dak dao dar dba dbb dbd dbe dbh dbk dbo dbr dda ddb ddd dde ddh ddk ddo ddr de- dea deb ded dee deh dek deo der dh- dha dhb dhd dhe dhh dhk dho dhr dka dkb dke dkk dko dkr doa dob dod doe doh dok doo dor dra drb drd dre drk dro drr eaa eab ead eae eah eak eao ear eba ebb ebd ebe ebh ebk ebo ebr ed- eda edb edd ede edh edk edo edr eea eeb eed eee eek eeo eer eha ehb ehd ehe ehh eho ehr eka ekb ekd eke ekh eko ekr eo- eoa eob eod eoe eoh eok eoo eor era erb erd ere erh erk ero err haa hab had hae hah hak hao har hba hbb hbd hbe hbh hbk hbo hbr hda hdb hdd hde hdh hdk hdo hdr he- hea heb hed hee heh hek heo her hha hhb hhd hhe hhh hhk hho hhr hka hkb hkd hkh hkk hko hkr hoa hob hod hoe hoh hok hoo hor hr- hra hrb hrd hre hrh hrk hro hrr ka- kaa kab kad kae kah kak kao kar kba kbb kbd kbe kbh kbk kbo kbr kda kdb kde kdh kdk kdo kdr ke- kea keb ked kee keh kek keo ker kha khe khh khk kho khr kkb kke kkh kkk kkr koa kob kod koe koh kok koo kor kra krd krk kro krr oaa oab oad oae oah oak oao oar ob- oba obb obd obe obh obk obo obr oda odb odd ode odh odo odr oea oeb oed oee oeh oeo oer oha ohd ohe ohh oho ohr oka okb okd oke okk oko okr oo- ooa oob ood ooh ook ooo oor or- ora orb ord ore orh ork oro orr ra- raa rab rad rae rah rak rao rar rba rbb rbd rbe rbh rbk rbo rbr rda rdb rdd rde rdh rdo rdr re- rea reb red ree reh rek reo rer rh- rha rhb rhd rhe rhh rho rhr rkb rke rkk rko roa rob rod roe roh rok roo ror rra rrb rrd rrh rrk rrr