-er a-a a-c aaa aac aad aae aao aar ac- aca acc acd ace aco acr ad- ada adc add ade ado adr aea aec aed aee aeo aer aoa aoc aod aoe aoo aor ar- ara arc ard are aro arr c-- caa cac cad cae cao car cca ccc ccd cce cco ccr cda cdc cdd cde cdo cdr ce- cea cec ced cee ceo cer co- coa coc cod coe coo cor cra crc crd cre cro crr daa dac dad dae dao dar dca dcc dcd dce dco dcr dda ddc ddd dde ddo ddr de- dea dec ded dee deo der doa doc dod doe doo dor dra drc drd dre dro drr eaa eac ead eae eao ear ec- eca ecc ecd ece eco ecr ed- eda edc edd ede edo edr eea eec eed eee eeo eer eo- eoa eoc eod eoe eoo eor era erc erd ere ero err oaa oac oad oae oao oar oc- oca occ ocd oco ocr oda odc odd ode odo odr oea oec oed oee oeo oer oo- ooa ooc ood ooo oor or- ora orc ord ore oro orr ra- raa rac rad rae rao rar rca rcc rcd rce rco rcr rda rdc rdd rde rdo rdr re- rea rec red ree reo rer roa roc rod roe roo ror rra rrc rrd rrr