思路：① 算每辆车到达时间 = (target - position) / speed；② 按位置降序排序；③ 单调递增栈：仅当当前时间 栈顶时间时压栈（新车队），否则合并。栈长即为车队数。可优化为用变量代替栈。
Nepal is a young democracy. It became a republic in 2008, after a civil war that killed more than 17,000 people and lasted 10 years.
，这一点在爱思助手下载最新版本中也有详细论述
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Ultrasonic speakers are lowered into the sea to test if they scare fish away