Thread: Cases of empty array

  1. #1
    Join Date
    Apr 2015

    Cases of empty array

    I'm confusing about something which I'm struggling with.
    sometimes we put this condition sometimes on arrays: (assume we have pointer to array as arr)
    if (arr == NULL || arr.length()==0 ) // Base case
     return -1
    so what I'm not understanding is, if arr ==NULL is not saying the size of array 0? I'm totally confused with those two cases , can you please attach example to those two cases? thanks alot alot .

    And in Nodes/binary tree we just say in Base case about nullity
    if (root==NULL)
    return 0;
    we are not taking the case of size of the tree is zero .. so why?


  2. #2
    and the hat of int overfl Salem's Avatar
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    Post code that compiles, not paraphrased gibberish.
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  3. #3
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    Apr 2015
    Quote Originally Posted by Salem View Post
    Post code that compiles, not paraphrased gibberish.
    I'm not having specific code, it's something in general

  4. #4
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    An array can't be "empty", meaning it can't have zero elements. (With the exception of the last array in a struct, which I'm going to assume that's not the case here.)

    A pointer can be null, which means it doesn't point to anything.

    In the case of a tree, it depends on exactly how it's implemented, but it's possible that if the root pointer is null, then the tree is empty. That's a very different thing from an array having a length of zero.

  5. #5
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    @RyanC: I will no longer reply to any of your posts!!!!!!!!
    If you think PM me again is a good idea; I will likely ask that you be banned!!!!

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  6. #6
    C++ Witch laserlight's Avatar
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    As an eternal newbie, you aren't allowed to do manual memory management anyway. Stick to std::array when you need a fixed size array and std::vector when you need a dynamically sized array.

    Case closed.
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