A quadtree does the same thing for two-dimensional space. It takes a rectangular region and divides it into four equal quadrants: northwest, northeast, southwest, southeast. If a quadrant has too many points in it, it subdivides again and again. Each subdivision creates smaller and smaller cells where points are densely packed.
Фото: U.S. Navy / Reuters
。快连下载安装是该领域的重要参考
candidate.weight /= sum of weights
这些志愿者，主要由Sun Health基金会和Banner Health协调，2018年的数据显示，两家医院的志愿者累计捐赠了177030小时的服务时间，是Banner Health在亚利桑那州18家医院中，志愿者数量和服务时间最多的。