The length of a circular runway is 400 meters. Xiaodong and Xiaoming set off at the same point on the runway in opposite directions at the same time. Xiaodong runs 6 meters per second, and Xiaoming runs 4 meters per second. Then, except for the first start, 3 minutes How many times did the two meet on the way?
一条环形跑道的长是400米，小东和小明在跑道上同一点沿相反方向同时出发，小东每秒跑6米，小明每秒跑4米，那么，除第一次出发以外，3分钟内两人在途中相遇多少次．
<result>4</result>