a-a a-b a-t aaa aab aad aaf aam aao aar aat ab- aba abb abd abf abm abo abr abt ad- ada adb add adf adm ado adr adt af- afa afb afd aff afm afo afr aft ama amb amd amf amm amo amr amt aoa aob aod aof aom aoo aor aot ar- ara arb ard arf arm aro arr art at- ata atb atd atf atm ato atr att baa bab bad baf bam bao bar bat bba bbb bbd bbf bbm bbo bbr bbt bda bdb bdd bdf bdm bdo bdr bdt bfa bfb bfd bff bfm bfo bfr bft bma bmb bmd bmf bmm bmo bmr bmt boa bob bod bof bom boo bor bot bra brb brd brf brm bro brr brt bta btb btd btf btm bto btr btt daa dab dad daf dam dao dar dat dba dbb dbd dbf dbm dbo dbr dbt dda ddb ddd ddf ddm ddo ddr ddt dfa dfb dfd dff dfm dfo dfr dft dma dmb dmd dmf dmm dmo dmr dmt doa dob dod dof dom doo dor dot dra drb drd drm dro drr drt dta dtb dtd dtf dtm dto dtr dtt faa fab fad faf fam fao far fat fba fbb fbd fbf fbm fbo fbr fbt fda fdb fdd fdf fdm fdo fdr fdt ffa ffd fff ffm ffo ffr fft fma fmb fmd fmf fmm fmo fmr fmt foa fob fof fom foo for fot fra frb frd frf frm fro frr frt fta ftb ftd ftf ftm fto ftr ftt m-f m-o m-r maa mab mad maf mam mao mar mat mba mbb mbd mbf mbm mbo mbr mbt mda mdb mdd mdf mdm mdo mdr mdt mfa mfb mfd mff mfm mfo mfr mft mma mmb mmd mmf mmm mmo mmr mmt moa mob mod mof mom moo mor mot mra mrb mrd mrf mrm mro mrr mrt mta mtb mtd mtf mtm mto mtr mtt oaa oab oad oaf oam oao oar oat ob- oba obb obd obf obm obo obr obt oda odb odd odf odm odo odr odt of- ofa ofb ofd off ofm ofo ofr oft om- oma omb omd omf omm omo omr omt oo- ooa oob ood oof oom ooo oor oot or- ora orb ord orf orm oro orr ort ot- ota otb otd otf otm oto otr ott ra- raa rab rad raf ram rao rar rat rba rbb rbd rbf rbm rbo rbr rbt rda rdb rdd rdf rdm rdo rdr rdt rfa rfb rfd rff rfm rfo rfr rft rma rmb rmd rmf rmm rmo rmr rmt roa rob rod rof rom roo ror rot rra rrb rrd rrf rrm rrr rrt rta rtb rtd rtf rtm rto rtr rtt taa tab tad taf tam tao tar tat tba tbb tbd tbf tbm tbo tbr tbt tda tdb tdd tdf tdm tdo tdr tdt tfa tfb tfd tff tfm tfo tfr tft tma tmb tmd tmf tmm tmo tmr tmt to- toa tob tod tof tom too tor tot tra trb trd trf trm tro trr trt tta ttb ttd ttf ttm tto ttr ttt