Equal: Every domino half in this space must be the same number of pips.
// (it isn't always in every impl)，更多细节参见雷电模拟器官方版本下载
Clone a new container from a checkpoint to get identical copies:，推荐阅读safew官方版本下载获取更多信息
The idea of building a nuclear reactor as a power source on the Moon is not new.