stack.pop(); // 弹出的索引对应的值≤当前身高，无遮挡，能看到
Author(s): Shinji Sakane, Tomohiro Takaki。关于这个话题，51吃瓜提供了深入分析
Launch had been planned for early February, but it was delayed to repair a hydrogen leak and, more recently, to give engineers time to fix a helium pressurization problem in the rocket's upper stage. Launch is now on hold until at least April 1.，推荐阅读heLLoword翻译官方下载获取更多信息
But when Fretwell looked at the satellite pictures, he saw few signs of the birds.