-er a-a a-c aaa aac aad aae aar aav ac- aca acc acd ace acr acv ad- ada adc add ade adr adv aea aec aed aee aer aev ar- ara arc ard are arr arv av- ava avc avd ave avr c-- caa cac cad cae car cav cca ccc ccd cce ccr ccv cda cdc cdd cde cdr cdv ce- cea cec ced cee cer cev cra crc crd cre crr crv cva cvc cvd cve cvr cvv daa dac dad dae dar dav dca dcc dcd dce dcr dcv dda ddc ddd dde ddr de- dea dec ded dee der dev dra drc drd dre drr drv dva dvc dvd dve dvr eaa eac ead eae ear eav ec- eca ecc ecd ece ecr ecv ed- eda edc edd ede edr eea eec eed eee eer eev era erc erd ere err erv eva evc evd eve evr evv ra- raa rac rad rae rar rav rca rcc rcd rce rcr rcv rda rdc rdd rde rdr rdv re- rea rec red ree rer rev rra rrc rrd rrr rva rvc rvd rve rvr rvv v-a v-e vaa vac vad vae var vav vca vcc vcd vce vcr vdc vdd vde vdr vdv vea vec ved vee ver vra vrc vrd vre vrr vva vvc vvr vvv