a-a a-b a-c a-t aaa aab aac aao aat aav ab- aba abb abc abo abt abv ac- aca acb acc aco act acv aoa aob aoc aoo aot aov at- ata atb atc ato att atv av- ava avb avc avo avt baa bab bac bao bat bav bba bbb bbc bbo bbt bca bcb bcc bco bct bcv boa bob boc boo bot bov bta btb btc bto btt btv bva bvb bvc bvo bvt bvv c-- caa cab cac cao cat cav cba cbb cbc cbo cbt cbv cca ccb ccc cco cct ccv co- coa cob coc coo cot cov cta ctb ctc cto ctt ctv cva cvb cvc cvo cvt cvv oaa oab oac oao oat oav ob- oba obb obc obo obt obv oc- oca ocb occ oco oct ocv oo- ooa oob ooc ooo oot oov ot- ota otb otc oto ott otv ov- ova ovb ovc ovo ovv taa tab tac tao tat tav tba tbb tbc tbo tbt tbv tca tcb tcc tco tct tcv to- toa tob toc too tot tov tta ttb ttc tto ttt ttv tva tvb tvc tvo tvt v-a vaa vab vac vao vat vav vba vbc vbo vbv vca vcc vco vct voa vob voc voo vot vov vta vtb vtc vto vtt vtv vva vvb vvc vvo vvt vvv