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How do I reverse an array of arrays?

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Contributed by Anonymous Monk on Sep 23, 2000 at 21:51 UTC
Q&A  > Data Structures

Answer: How do I reverse an array of arrays?
contributed by merlyn

First, there's no array of arrays. The closest Perl has is an array of arrayrefs.

Second, "reverse" along what axis? The top level is simple:

@reversed = reverse @array;

The second level is also pretty easy:

@second_level_reversed = map [reverse @$_], @array;
And you can add a reverse ahead of map to do them both.

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