a-a a-b a-i aaa aab aad aaf aai aao aar aas aau ab- aba abb abd abf abi abo abr abs abu ad- ada adb add adf adi ado adr ads adu af- afa afb afd aff afi afo afr afs afu ai- aia aib aid aif aii aio air ais aiu aoa aob aod aof aoi aoo aor aos aou ar- ara arb ard arf ari aro arr ars aru as- asa asb asd asf asi aso asr ass asu au- aua aub aud auf aui auo aur aus b-u baa bab bad baf bai bao bar bas bau bba bbb bbd bbf bbi bbo bbr bbs bbu bda bdb bdd bdf bdi bdo bdr bds bdu bfa bfb bfd bff bfi bfo bfr bfs bfu bi- bia bib bid bif bii bio bir bis biu boa bob bod bof boi boo bor bos bou bra brb brd brf bri bro brr brs bru bsa bsb bsd bsf bsi bso bsr bss bsu bua bub bud buf bui buo bur bus buu daa dab dad daf dai dao dar das dau dba dbb dbd dbf dbi dbo dbr dbs dbu dda ddb ddd ddf ddi ddo ddr dds ddu dfa dfb dfd dff dfi dfo dfr dfs dfu di- dia dib did dif dii dio dir dis diu doa dob dod dof doi doo dor dos dou dra drb drd dri dro drr drs dru dsa dsb dsd dsf dsi dso dsr dss dsu dua dub dud duf dui duo dur dus faa fab fad faf fai fao far fas fau fba fbb fbd fbf fbi fbo fbr fbs fbu fda fdb fdd fdf fdi fdo fdr fds fdu ffa ffd fff ffi ffo ffr ffs ffu fia fib fid fif fii fir fis fiu foa fob fof foi foo for fos fou fra frb frd frf fri fro frr frs fru fsa fsb fsd fsf fsi fso fsr fss fsu fua fub fud fuf fui fuo fur fus fuu i-d i-f ia- iaa iab iad iaf iai iao iar ias iau iba ibb ibd ibf ibi ibo ibr ibs ibu ida idb idd idf idi ido idr ids idu ifa ifb ifd iff ifi ifo ifr ifs ifu iia iib iid iif iii iio iir iis iiu io- ioa iob iod iof ioi ioo ior ios iou ir- ira irb ird irf iri iro irr irs iru is- isa isb isd isf isi iso isr iss isu iu- iua iub iud iui iur ius o-i oaa oab oad oaf oai oao oar oas oau ob- oba obb obd obf obi obo obr obs obu oda odb odd odf odi odo odr ods odu of- ofa ofb ofd off ofi ofo ofr ofs ofu oia oib oid oif oii oio oir ois oiu oo- ooa oob ood oof ooi ooo oor oos or- ora orb ord orf ori oro orr ors oru os- osa osb osd osf osi oso osr oss osu ou- oua oud ouf oui ouo our ous ra- raa rab rad raf rai rao rar ras rau rba rbb rbd rbf rbi rbo rbr rbs rbu rda rdb rdd rdf rdi rdo rdr rds rdu rfa rfb rfd rff rfi rfo rfr rfs rfu ria rib rid rif rii rio rir ris roa rob rod rof roi roo ror ros rou rra rrb rrd rrf rri rrr rrs rru rsa rsb rsd rsf rsi rso rsr rss rsu rua rub rud ruf rui ruo rur rus ruu saa sab sad saf sai sao sar sas sau sba sbb sbd sbf sbi sbo sbr sbs sbu sda sdb sdd sdf sdi sdo sdr sds sdu sfa sfb sfd sff sfi sfo sfr sfs sfu sia sib sid sif sii sio sir sis siu soa sob sod sof soi soo sor sos sou sr- sra srb srd srf sri sro srr srs ss- ssa ssb ssd ssf ssi sso ssr sss ssu sua sub sud suf sui suo sur sus suu ua- uaa uab uad uaf uai uao uar uas uau uba ubb ubf ubi ubo ubr ubs ubu uda udb udd udf udi udo udr uds udu ufa ufd uff ufi ufo ufr ufs ufu uia uib uid uif uii uio uir uis uiu uoa uob uod uoo uor uos ur- ura urb urd urf uri uro urr urs uru usa usb usd usf usi uso usr uss usu uua uur uus uuu