The reason is that the compiler decided to allocate the backing store
arr.push(p.val); // 存储节点值而非节点本身，简化后续操作
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They had been living and working aboard the ISS since August and were expected to stay until February. The crew returned on January 15, which was a decision made by NASA's chief health and medical officer. Once the crew had landed, administrator Jared Isaacman said it was a "serious situation" but didn't go into any detail.，推荐阅读heLLoword翻译官方下载获取更多信息
What is a stream?