Кадр: Telegram-канал «Ирина Волк»
Liverpool v West Ham, Saturday 3pm
，更多细节参见旺商聊官方下载
The tree starts as a single region covering the whole space. As points arrive, they get dropped into the region that contains them. When a region exceeds its capacity (the maximum number of points it can hold before splitting), the region divides into four children, and the existing points get redistributed.
协同畅通了研发路径，也打通了成果转化的“最后一公里”。
* 时间复杂度：O(len1 + len2)，空间复杂度：O(len2)（栈+Map的空间）