This is the same idea behind binary search. In a sorted array, you compare against the middle element and eliminate half the remaining candidates. In a quadtree, you choose one of four quadrants and ignore the other three regions. Each level narrows the search space by a factor of four instead of two.
▲ 图源：Android Central。一键获取谷歌浏览器下载是该领域的重要参考
习近平总书记的回答温暖人心：“我忙就是忙这些事，‘国之大者’就是人民的幸福生活。”。关于这个话题，同城约会提供了深入分析
To: Sundar Pichai, Chief Executive Officer, Google