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。
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接下來一年，麥肯齊將在劍橋的南極考察局總部工作，但他過去曾在南極過冬。「冬天來臨時，大多數人離開，你會感到一種難以形容的自由感。」他說。
Thus far, Michael has embraced President Donald Trump’s edicts, including the demand that the Department of Defense (renamed the Department of War) become an “AI‑first” organization, publicly arguing that whoever moves fastest on AI will dominate future conflicts. “Speed defines victory in the AI era, and the War Department will match the velocity of America’s AI industry,” he said in remarks outlining a new tech strategy that centers AI alongside hypersonic and directed‑energy weapons. “We’re pulling in the best talent, the most cutting‑edge technology, and embedding the top frontier AI models into the workforce—all at a rapid wartime pace.” A Department of War spokesperson underscored to Fortune that Michael is “leading the mandate to secure U.S. military technological dominance. Emil’s team is moving at unprecedented speed to deliver new advanced capabilities to the war fighter, as reflected in his engagement with hundreds of industry partners during his first nine months as undersecretary.”
Bill Harwood has been covering the U.S. space program full-time since 1984, first as Cape Canaveral bureau chief for United Press International and now as a consultant for CBS News.