a-a a-b a-c aaa aab aac aad aag aao aar ab- aba abb abc abd abg abo abr ac- aca acb acc acd acg aco acr ad- ada adb adc add adg ado adr ag- aga agb agc agd agg ago agr aoa aob aoc aod aog aoo aor ar- ara arb arc ard arg aro arr baa bab bac bad bag bao bar bba bbb bbc bbd bbg bbo bbr bca bcb bcc bcd bcg bco bcr bda bdb bdc bdd bdg bdo bdr bga bgb bgc bgd bgg bgo bgr boa bob boc bod bog boo bor bra brb brd brg bro brr c-- caa cab cac cad cag cao car cba cbb cbc cbd cbg cbo cbr cca ccb ccc ccd ccg cco ccr cda cdb cdc cdd cdg cdo cdr cga cgb cgc cgd cgg cgo cgr co- coa cob coc cod cog coo cor cra crb crc crd crg cro crr daa dab dac dad dag dao dar dba dbb dbc dbd dbg dbo dbr dca dcb dcc dcd dcg dco dcr dda ddb ddc ddd ddg ddo ddr dga dgc dgd dgg dgr doa dob doc dod dog doo dor dra drb drc drd drg dro drr g-d gaa gab gac gad gag gao gar gba gbc gbd gbg gbo gbr gca gcb gcc gcd gcg gco gcr gda gdb gdc gdd gdo gdr gga ggb ggc ggd ggg ggo ggr goa gob goc god gog goo gor gra grb grc grd grg gro grr oaa oab oac oad oag oao oar ob- oba obb obc obd obg obo obr oc- oca ocb occ ocd ocg oco ocr oda odb odc odd odg odo odr oga ogc ogd ogg ogo oo- ooa oob ooc ood oog ooo oor or- ora orb orc ord org oro orr ra- raa rab rac rad rag rao rar rba rbb rbc rbd rbg rbo rbr rca rcb rcc rcd rcg rco rcr rda rdb rdc rdd rdg rdo rdr rga rgb rgc rgd rgg rgo rgr roa rob roc rod rog roo ror rra rrb rrc rrd rrg rrr