-er a-a a-b a-c aaa aab aac aad aae aag aao aar aau ab- aba abb abc abd abe abg abo abr abu ac- aca acb acc acd ace acg aco acr acu ad- ada adb adc add ade adg ado adr adu aea aeb aec aed aee aeg aeo aer aeu ag- aga agb agc agd age agg ago agr agu aoa aob aoc aod aoe aog aoo aor aou ar- ara arb arc ard are arg aro arr aru au- aua aub auc aud aue aug auo aur b-u baa bab bac bad bae bag bao bar bau bba bbb bbc bbd bbe bbg bbo bbr bbu bca bcb bcc bcd bce bcg bco bcr bcu bda bdb bdc bdd bde bdg bdo bdr bdu be- bea beb bec bed bee beg beo ber beu bga bgb bgc bgd bge bgg bgo bgr bgu boa bob boc bod boe bog boo bor bou bra brb brd bre brg bro brr bru bua bub buc bud bue bug buo bur buu c-- caa cab cac cad cae cag cao car cau cba cbb cbc cbd cbe cbg cbo cbr cbu cca ccb ccc ccd cce ccg cco ccr ccu cda cdb cdc cdd cde cdg cdo cdr cdu ce- cea ceb cec ced cee ceg ceo cer ceu cga cgb cgc cgd cge cgg cgo cgr cgu co- coa cob coc cod coe cog coo cor cou cra crb crc crd cre crg cro crr cru cua cub cuc cud cue cug cuo cur cuu daa dab dac dad dae dag dao dar dau dba dbb dbc dbd dbe dbg dbo dbr dbu dca dcb dcc dcd dce dcg dco dcr dcu dda ddb ddc ddd dde ddg ddo ddr ddu de- dea deb dec ded dee deg deo der deu dga dgc dgd dge dgg dgr dgu doa dob doc dod doe dog doo dor dou dra drb drc drd dre drg dro drr dru dua dub duc dud due dug duo dur eaa eab eac ead eae eag eao ear eau eba ebb ebc ebd ebe ebg ebo ebr ebu ec- eca ecb ecc ecd ece ecg eco ecr ecu ed- eda edb edc edd ede edg edo edr edu eea eeb eec eed eee eeg eeo eer ega egb egc egd ege egg ego egr egu eo- eoa eob eoc eod eoe eog eoo eor eou era erb erc erd ere erg ero err eru eu- eua eub euc eud eue eug eur g-d gaa gab gac gad gae gag gao gar gau gba gbc gbd gbe gbg gbo gbr gbu gca gcb gcc gcd gce gcg gco gcr gcu gda gdb gdc gdd gde gdo gdr gdu ge- gea geb gec ged gee geg geo ger geu gga ggb ggc ggd ggg ggo ggr ggu goa gob goc god goe gog goo gor gou gra grb grc grd gre grg gro grr gru gu- gua gub guc gud gue gug guo gur guu oaa oab oac oad oae oag oao oar oau ob- oba obb obc obd obe obg obo obr obu oc- oca ocb occ ocd ocg oco ocr ocu oda odb odc odd ode odg odo odr odu oea oeb oec oed oee oeg oeo oer oga ogc ogd oge ogg ogo oo- ooa oob ooc ood oog ooo oor or- ora orb orc ord ore org oro orr oru ou- oua ouc oud oue ouo our ra- raa rab rac rad rae rag rao rar rau rba rbb rbc rbd rbe rbg rbo rbr rbu rca rcb rcc rcd rce rcg rco rcr rcu rda rdb rdc rdd rde rdg rdo rdr rdu re- rea reb rec red ree reg reo rer reu rga rgb rgc rgd rge rgg rgo rgr roa rob roc rod roe rog roo ror rou rra rrb rrc rrd rrg rrr rru rua rub ruc rud rue rug ruo rur ruu ua- uaa uab uac uad uae uag uao uar uau uba ubb ubc ube ubg ubo ubr ubu uca ucb ucc ucd uce ucg uco ucr ucu uda udb udc udd ude udg udo udr udu uea ueb uec ued uee ueg uer uga ugb ugc uge ugg ugo ugr ugu uoa uob uoc uod uoe uog uoo uor ur- ura urb urc urd ure urg uro urr uru uua uuc uue uug uur uuu