-er a-a a-c aaa aac aad aae aaf aar ac- aca acc acd ace acf acr ad- ada adc add ade adf adr aea aec aed aee aef aer af- afa afc afd afe aff afr ar- ara arc ard are arf arr c-- caa cac cad cae caf car cca ccc ccd cce ccf ccr cda cdc cdd cde cdf cdr ce- cea cec ced cee cef cer cfa cfc cfd cfe cff cfr cra crc crd cre crf crr daa dac dad dae daf dar dca dcc dcd dce dcf dcr dda ddc ddd dde ddf ddr de- dea dec ded dee def der dfa dfc dfd dfe dff dfr dra drc drd dre drr eaa eac ead eae eaf ear ec- eca ecc ecd ece ecf ecr ed- eda edc edd ede edf edr eea eec eed eee eef eer ef- efa efc efd efe eff efr era erc erd ere erf err faa fac fad fae faf far fca fcc fcd fce fcf fcr fda fdc fdd fde fdf fdr fea fec fed fee fef fer ffa ffc ffd ffe fff ffr fra frc frd fre frf frr ra- raa rac rad rae raf rar rca rcc rcd rce rcf rcr rda rdc rdd rde rdf rdr re- rea rec red ree ref rer rfa rfc rfd rfe rff rfr rra rrc rrd rrf rrr