One of the things that we discussed was this type of imagery here where you have vertically these pillars, if you will, or we could even call--the more I sort of looked at this--sort of call them tree trunks almost.

我们讨论的问题之一是这里的这种意象，这些垂直的柱子，如果你愿意的话，我们可以称之为，我越看越觉得称之为树干比较好。

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So if on each iteration of merging I'm doing eight things or more generally, N. That then begs the question, how many levels of this tree are there actually?

可见对于合并我需要迭代8次,一般情况下是N，这取决于具体问题，那么在这棵树中一共有多少层呢？

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