思路：倒序遍历 2 倍长度 + 取模模拟循环 + 单调栈。用 i % len 映射到真实索引，仅当 i < len 时记录答案。
How little time it takes to watch a micro-drama is exactly what seems to attract viewers.
，更多细节参见51吃瓜
Agar’s low viscosity also makes it easy to pour into Petri dishes, and its transparency permits observation of microbes growing on its surface.7 Also aiding in this is its low syneresis (extrusion of water from the gel), guaranteeing less surface “sweating”: Once a plate is inoculated, bacterial colonies stay in place and do not mix.，详情可参考夫子
Multilingual, TDT decoder