a-a a-b aaa aab aad aah aao aar ab- aba abb abd abh abo abr ad- ada adb add adh ado adr aha ahb ahd ahh aho ahr aoa aob aod aoh aoo aor ar- ara arb ard arh aro arr baa bab bad bah bao bar bba bbb bbd bbh bbo bbr bda bdb bdd bdh bdo bdr bha bhb bhd bhh bho bhr boa bob bod boh boo bor bra brb brd brh bro brr daa dab dad dah dao dar dba dbb dbd dbh dbo dbr dda ddb ddd ddh ddo ddr dh- dha dhb dhd dhh dho dhr doa dob dod doh doo dor dra drb drd dro drr haa hab had hah hao har hba hbb hbd hbh hbo hbr hda hdb hdd hdh hdo hdr hha hhb hhd hhh hho hhr hoa hob hod hoh hoo hor hr- hra hrb hrd hrh hro hrr oaa oab oad oah oao oar ob- oba obb obd obh obo obr oda odb odd odh odo odr oha ohd ohh oho ohr oo- ooa oob ood ooh ooo oor or- ora orb ord orh oro orr ra- raa rab rad rah rao rar rba rbb rbd rbh rbo rbr rda rdb rdd rdh rdo rdr rh- rha rhb rhd rhh rho rhr roa rob rod roh roo ror rra rrb rrd rrh rrr