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FT Digital Edition，详情可参考夫子
A quadtree reduces this: rebuild the tree each frame, and for each object, query only the nearby region. Objects in distant quadrants are never compared.，更多细节参见同城约会
（本报记者赵成、吴丹、朱隽、王昊男、侯琳良、杨文明、王云娜、刘军国、李心萍、寇江泽、李林蔚、常钦、刘新吾、郑洋洋、李俊杰）