-er a-a a-c aaa aac aad aae aak aap aar ac- aca acc acd ace ack acp acr ad- ada adc add ade adk adp adr aea aec aed aee aek aep aer aka akc akd ake akk akp akr ap- apa apc apd ape apk app apr ar- ara arc ard are ark arp arr c-- caa cac cad cae cak cap car cca ccc ccd cce cck ccp ccr cda cdc cdd cde cdk cdp cdr ce- cea cec ced cee cek cep cer cka ckc ckd cpa cpc cpd cpe cpk cpp cpr cra crc crd cre crk crp crr daa dac dad dae dak dap dar dca dcc dcd dce dck dcp dcr dda ddc ddd dde ddk ddp ddr de- dea dec ded dee dek dep der dka dkc dke dkk dkp dkr dpa dpc dpd dpe dpk dpp dpr dra drc drd dre drk drp drr eaa eac ead eae eak eap ear ec- eca ecc ecd ece eck ecr ed- eda edc edd ede edk edp edr eea eec eed eee eek eep eer eka ekc ekd eke ekp ekr ep- epa epc epd epe epp epr era erc erd ere erk erp err ka- kaa kac kad kae kak kap kar kca kcc kcd kce kck kcp kcr kda kdc kde kdk kdp kdr ke- kea kec ked kee kek kep ker kkc kke kkk kkp kkr kpa kpc kpd kpe kpk kpp kpr kra krc krd krk krp krr p-p paa pac pad pae pak pap par pca pcc pcd pce pck pcp pcr pda pdc pdd pde pdk pdp pdr pea pec ped pee pek pep per pka pkc pkd pke pkp pkr ppa ppc ppd ppe ppk ppp ppr pra prc prd pre prk prp prr ra- raa rac rad rae rak rap rar rca rcc rcd rce rcp rcr rda rdc rdd rde rdp rdr re- rea rec red ree rek rep rer rkc rke rkk rkp rpa rpc rpd rpe rpk rpp rpr rra rrc rrd rrk rrp rrr