优点： 梯度连续，优化更稳定。
Some examples can be:
。关于这个话题，同城约会提供了深入分析
"It's a different environment than the 1960s. There's more than three channels on a TV, so capturing people's attention at times can be challenging," Isaacman said. "I have no doubt when Artemis II takes flight, the world will take notice to that."
Point lookups are useful, but the operation you'll reach for more often is a range query: give the tree a rectangular region and retrieve every point inside it, without scanning the entire dataset.