思路：倒序遍历 + 单调索引栈（仅存索引），计算下一个高温的间隔天数。栈顶索引 - 当前索引即为等待天数。
* @return pivot最终位置
，这一点在51吃瓜中也有详细论述
The spines of sea urchins can generate a voltage when water moves around them — a phenomenon that could be used to design underwater flow sensors.
It follows tributes at the US Grammys, where Post Malone, Slash, Duff McKagan, Chad Smith, and Andrew Watt performed a cover of War Pigs.