A circular runway, Xiao Gao, Xiao Si, and Xiao Bei start from point A of the runway at the same time, Xiao Gao advances clockwise, Xiao Si and Xiao Bei advance counterclockwise, Xiao Gao meets Xiao Si for the first time when he advances 503 meters, After the encounter, Xiao Gao continued to move forward and walked 503 meters before meeting Xiao Bei for the first time. If Xiao Gao increased his speed to three times the original speed when starting out, Xiao Gao walked 1509 meters before meeting Xiao Bei for the first time. What is the circumference of the circular runway.
一个环形跑道，小高、小思、小北三人同时从跑道A点出发，小高按顺时针方向前进，小思、小北按逆时针方向前进，小高前进503米时与小思第一次相遇，相遇后小高继续前进又走了503米后与小北第一次相遇，若出发时小高把自己的速度提高到原来的3倍，则小高走了1509米才与小北第一次相遇，则环形跑道周长是多少．
<gadget id="calculator">1_006 + 1_006</gadget>
<output>2_012</output>

<result>2_012</result>