Today there are 6 teams in a single round robin match, every two teams play only one game, the winner gets 3 points, the loser gets 0 points, and each draw gets 1 point. At the end of the game, the scores of each team from high to low are exactly arithmetic difference series (the difference between the scores of two adjacent teams is equal), and the third place gets 8 points. How many draws were there in this match?
今有6支球队进行单循环赛，每两个队赛且仅赛一场，胜者得3分，负者得0分，平局各得l分．比赛结束，各队得分由高到低恰好是等差数列(排名相邻两队得分差相等)，其中第三名得8分．这次比赛中平局共有几场？
<gadget id="calculator">12 + 10 + 8 + 6 + 4 + 2</gadget>
<output>42</output>

<gadget id="calculator">45 - 42</gadget>
<output>3</output>

<result>3</result>