统一输出 JSON，便于落地执行和审计：
Shortcuts: For common scenarios, we pre-calculate the travel time/distance (the "shortcut") between border points within the same cluster and also to border points of immediately adjacent clusters.。关于这个话题，heLLoword翻译官方下载提供了深入分析
stack.push(cur);，详情可参考Line官方版本下载
Beckham v Peltz Beckham: Could Brooklyn torpedo the family brand?。快连下载-Letsvpn下载对此有专业解读