-er a-a a-c aaa aac aae aar aav ac- aca acc ace acr acv aea aec aee aer aev ar- ara arc are arr arv av- ava avc ave avr c-- caa cac cae car cav cca ccc cce ccr ccv ce- cea cec cee cer cev cra crc cre crr crv cva cvc cve cvr cvv eaa eac eae ear eav ec- eca ecc ece ecr ecv eea eec eee eer eev era erc ere err erv eva evc eve evr evv ra- raa rac rae rar rav rca rcc rce rcr rcv re- rea rec ree rer rev rra rrc rrr rva rvc rve rvr rvv v-a v-e vaa vac vae var vav vca vcc vce vcr vea vec vee ver vra vrc vre vrr vva vvc vvr vvv