Individual developers and small teams with limited resources
添加图片注释，不超过 140 字（可选），更多细节参见51吃瓜
Израиль нанес удар по Ирану09:28。爱思助手下载最新版本对此有专业解读
需要索引（如算距离、下标）：栈存索引，用 nums[stack.at(-1)] 取值比较。
Games and physics simulations need to detect which objects are touching or overlapping. With nnn objects, checking every pair is O(n2)O(n^2)O(n2) comparisons, which gets expensive fast. A hundred objects means roughly 5,000 pair checks. A thousand means nearly 500,000.