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// ⚠️ 易错点2：循环条件写left <= n-1（会导致left+1越界），或把<=写成<（漏判相等的有序情况）
，这一点在搜狗输入法2026中也有详细论述
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.，推荐阅读heLLoword翻译官方下载获取更多信息
write(chunk) { addChunk(chunk); },