a-a a-b a-i a-t aaa aab aad aaf aai aao aar aas aat ab- aba abb abd abf abi abo abr abs abt ad- ada adb add adf adi ado adr ads adt af- afa afb afd aff afi afo afr afs aft ai- aia aib aid aif aii aio air ais ait aoa aob aod aof aoi aoo aor aos aot ar- ara arb ard arf ari aro arr ars art as- asa asb asd asf asi aso asr ass ast at- ata atb atd atf ati ato atr ats att baa bab bad baf bai bao bar bas bat bba bbb bbd bbf bbi bbo bbr bbs bbt bda bdb bdd bdf bdi bdo bdr bds bdt bfa bfb bfd bff bfi bfo bfr bfs bft bi- bia bib bid bif bii bio bir bis bit boa bob bod bof boi boo bor bos bot bra brb brd brf bri bro brr brs brt bsa bsb bsd bsf bsi bso bsr bss bst bta btb btd btf bti bto btr bts btt daa dab dad daf dai dao dar das dat dba dbb dbd dbf dbi dbo dbr dbs dbt dda ddb ddd ddf ddi ddo ddr dds ddt dfa dfb dfd dff dfi dfo dfr dfs dft di- dia dib did dif dii dio dir dis dit doa dob dod dof doi doo dor dos dot dra drb drd dri dro drr drs drt dsa dsb dsd dsf dsi dso dsr dss dst dta dtb dtd dtf dti dto dtr dts dtt faa fab fad faf fai fao far fas fat fba fbb fbd fbf fbi fbo fbr fbs fbt fda fdb fdd fdf fdi fdo fdr fds fdt ffa ffd fff ffi ffo ffr ffs fft fia fib fid fif fii fir fis fit foa fob fof foi foo for fos fot fra frb frd frf fri fro frr frs frt fsa fsb fsd fsf fsi fso fsr fss fst fta ftb ftd ftf fti fto ftr fts ftt i-d i-f ia- iaa iab iad iaf iai iao iar ias iat iba ibb ibd ibf ibi ibo ibr ibs ibt ida idb idd idf idi ido idr ids idt ifa ifb ifd iff ifi ifo ifr ifs ift iia iib iid iif iii iio iir iis iit io- ioa iob iod iof ioi ioo ior ios iot ir- ira irb ird irf iri iro irr irs irt is- isa isb isd isf isi iso isr iss ist ita itb itd itf iti ito its itt o-i oaa oab oad oaf oai oao oar oas oat ob- oba obb obd obf obi obo obr obs obt oda odb odd odf odi odo odr ods odt of- ofa ofb ofd off ofi ofo ofr ofs oft oia oib oid oif oii oio oir ois oit oo- ooa oob ood oof ooi ooo oor oos oot or- ora orb ord orf ori oro orr ors ort os- osa osb osd osf osi oso osr oss ost ot- ota otb otd otf oti oto otr ots ott ra- raa rab rad raf rai rao rar ras rat rba rbb rbd rbf rbi rbo rbr rbs rbt rda rdb rdd rdf rdi rdo rdr rds rdt rfa rfb rfd rff rfi rfo rfr rfs rft ria rib rid rif rii rio rir ris rit roa rob rod rof roi roo ror ros rot rra rrb rrd rrf rri rrr rrs rrt rsa rsb rsd rsf rsi rso rsr rss rst rta rtb rtd rtf rti rto rtr rts rtt saa sab sad saf sai sao sar sas sat sba sbb sbd sbf sbi sbo sbr sbs sbt sda sdb sdd sdf sdi sdo sdr sds sdt sfa sfb sfd sff sfi sfo sfr sfs sft sia sib sid sif sii sio sir sis sit soa sob sod sof soi soo sor sos sot sr- sra srb srd srf sri sro srr srs srt ss- ssa ssb ssd ssf ssi sso ssr sss sst sta stb std stf sti sto str sts stt taa tab tad taf tai tao tar tas tat tba tbb tbd tbf tbi tbo tbr tbs tbt tda tdb tdd tdf tdi tdo tdr tds tdt tfa tfb tfd tff tfi tfo tfr tfs tft tia tib tid tif tii tio tir tis tit to- toa tob tod tof toi too tor tos tot tra trb trd trf tri tro trr trs trt tsa tsb tsd tsf tsi tso tsr tss tst tta ttb ttd ttf tti tto ttr tts ttt