В Финляндии предупредили об опасном шаге ЕС против России09:28
Quadtrees are everywhere spatial data exists. Mapping services use quadtree-like tile pyramids to serve map tiles at different zoom levels (Bing's quadkey system, for example, addresses tiles as base-4 paths). Game engines use them for collision detection and visibility culling. Geographic information systems use spatial indexes to store and query spatial datasets. PostGIS uses GiST indexes (R-tree-style) for spatial queries on geometries, while PostgreSQL's core supports quadtree-like SP-GiST indexes for certain data types like points.，这一点在im钱包官方下载中也有详细论述
。关于这个话题，同城约会提供了深入分析
h = (union alloc_header*)(((char*)h)+(16LL<<j));
--------------------------------，更多细节参见safew官方版本下载