-er a-a a-c a-t aaa aac aad aae aaf aak aar aat ac- aca acc acd ace acf ack acr act ad- ada adc add ade adf adk adr adt aea aec aed aee aef aek aer aet af- afa afc afd afe aff afk afr aft aka akc akd ake akk akr ar- ara arc ard are arf ark arr art at- ata atc atd ate atf atr att c-- caa cac cad cae caf cak car cat cca ccc ccd cce ccf cck ccr cct cda cdc cdd cde cdf cdk cdr cdt ce- cea cec ced cee cef cek cer cet cfa cfc cfd cfe cff cfk cfr cft cka ckc ckd ckt cra crc crd cre crf crk crr crt cta ctc ctd cte ctf ctk ctr ctt daa dac dad dae daf dak dar dat dca dcc dcd dce dcf dck dcr dct dda ddc ddd dde ddf ddk ddr ddt de- dea dec ded dee def dek der det dfa dfc dfd dfe dff dfk dfr dft dka dkc dke dkk dkr dkt dra drc drd dre drk drr drt dta dtc dtd dte dtf dtk dtr dtt eaa eac ead eae eaf eak ear eat ec- eca ecc ecd ece ecf eck ecr ect ed- eda edc edd ede edf edk edr edt eea eec eed eee eef eek eer eet ef- efa efc efd efe eff efr eft eka ekc ekd eke ekf ekr ekt era erc erd ere erf erk err ert eta etc etd ete etf etk etr ett faa fac fad fae faf fak far fat fca fcc fcd fce fcf fck fcr fct fda fdc fdd fde fdf fdk fdr fdt fea fec fed fee fef fek fer fet ffa ffc ffd ffe fff ffk ffr fft fka fkc fkf fkk fkt fra frc frd fre frf frk frr frt fta ftc ftd fte ftf ftk ftr ftt k-t ka- kaa kac kad kae kaf kak kar kat kca kcc kcd kce kck kcr kct kda kdc kde kdf kdk kdr kdt ke- kea kec ked kee kef kek ker ket kfa kfc kfd kff kkc kke kkk kkr kkt kra krc krd krf krk krr krt kta ktc kte ktf ktk ktr ktt ra- raa rac rad rae raf rak rar rat rca rcc rcd rce rcf rcr rct rda rdc rdd rde rdf rdr rdt re- rea rec red ree ref rek rer ret rfa rfc rfd rfe rff rfk rfr rft rkc rke rkf rkk rkt rra rrc rrd rrf rrk rrr rrt rta rtc rtd rte rtf rtk rtr rtt taa tac tad tae taf tak tar tat tca tcc tcd tce tcf tck tcr tct tda tdc tdd tde tdf tdk tdr tdt te- tea tec ted tee tef tek ter tet tfa tfc tfd tfe tff tfk tfr tft tka tkc tke tkk tkr tkt tra trc trd tre trf trk trr trt tta ttc ttd tte ttf ttk ttr ttt