pass 3D array

This is a discussion on pass 3D array within the C Programming forums, part of the General Programming Boards category; For 2D array, we can pass the array to other function like: Code: int array[5][10]; ... func((int *)array, 5, 10); ...

  1. #1
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    pass 3D array

    For 2D array, we can pass the array to other function like:
    Code:
    int array[5][10];
    ...
    func((int *)array, 5, 10);
    ...
    ...
    int func(int *array, int x, int y) {
        *(array + y * 0 + 8) = 1000;   /*change array[0][8]*/
        *(array + y * 1 + 8) = 2000;   /*change array[1][8]*/
    }
    I' m wondering how we can pass a 3D array...

  2. #2
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    > For 2D array, we can pass the array to other function like:
    Since your attempt at 2D is wrong, 3D will be hopeless.

    If you have
    int array[5][10];

    The prototype for a function is
    void func ( int array[5][10] );

    A call to this function would be
    func ( array );

    And the implementation would be
    Code:
    void func ( int array[5][10] ) {
      array[0][0] = 0;
    }
    Notice how simply copy/pasting the array into the function parameter is all you need to do.
    Also notice the complete lack of any * or & operators anywhere in the code.

    Pedantically, you can reduce
    void func ( int array[5][10] );
    to
    void func ( int array[][10] );
    since C doesn't need to know the size of the first dimension of the array.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
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  3. #3
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    What if we don't know exactly the size of array we gonna pass to func()?
    How can we create a func() which can accept any size of array?

  4. #4
    and the hat of wrongness Salem's Avatar
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    http://www.eskimo.com/~scs/C-faq/q6.19.html

    int a[5][10];
    int b[100][10];
    Can both be passed to void func ( int array[][10] );
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

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