2. 按步长分组，对每组进行插入排序
The spatial view (the grid of rectangles) and the tree view (the hierarchy of nodes) represent the same structure. Searching for a point means walking down the tree: at each node, you check which of the four children contains your target coordinate and recurse into that child. You never visit the other three.
，详情可参考51吃瓜
# What is the lesson here?
The planetary parade was photographed from Worth Matravers
Москвичи пожаловались на зловонную квартиру-свалку с телами животных и тараканами18:04