That is basically saying, given some collection of data, I want to have again a looping mechanism, where now my process is, walk through this, the collection one element at a time. And for that, we have a particular construct, called a FOR loop.

现在我的过程就是,通过一个个访问这个集合中,的元素的方式，来遍历这个集合,为了达到这个目的，我们有一个特定的结构，成为FOR循环。

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