// First, we acquire a reader that gives an exclusive lock
* - this.stack：单调递减栈，存储「价格对应的索引」，栈顶→栈底索引对应的价格单调递减
，这一点在im钱包官方下载中也有详细论述
Notably, the round remains open, and OpenAI expects more investors to join as it proceeds.
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Example: deleting a passkey in Google Password Manager