Well, it looks like it took 1 in this case or it involves-- we can put it another way, merging those two lists involved looking at two numbers, 1, 2, and that's it.

在这种情况下看起来只用了1次-,我们可以从另一个角度看，合并这两个列表涉及到了,2个数字，1，2，就是这样。

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