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Thread: How do I reverse an ArrayList ?

  1. #1
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    Default How do I reverse an ArrayList ?

    I am trying to figure out how to write a method that will reverse an ArrayList. I can't use collections.reverse(). I'm lost, my teacher speaks broken English so I'm basically on my own here. I think that I should use a for loop, something like this:

    for (int index = arrayList.size(); index = 0; index--)

    But, I don't understand how to make it return the reversed arrayList. Any help is appreciated.


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: How do I reverse an ArrayList ?

    You could do it in a loop. Take a piece of paper and a pencil, draw some objects on a row representing the objects in the arraylist. Use indexes/pointers (one at each end) and work out the logic for reversing the contents.
    If you don't understand my answer, don't ignore it, ask a question.

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