array pointer question

This is a discussion on array pointer question within the C Programming forums, part of the General Programming Boards category; Hey there. I'm new to here so bear with me. The question: If you have a declaration such as: int ...

  1. #1
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    array pointer question

    Hey there. I'm new to here so bear with me. The question:

    If you have a declaration such as: int a[15];

    which experssion would be a pointer to the 3rd element?

    a+2
    or
    $(a+2)

    I'm a little confused. any info would be great

  2. #2
    Just Lurking Dave_Sinkula's Avatar
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    Code:
       int *ptr;
       ptr = a + 2;
       /* or */
       ptr = &a[2];
    7. It is easier to write an incorrect program than understand a correct one.
    40. There are two ways to write error-free programs; only the third one works.*

  3. #3
    and the hat of wrongness Salem's Avatar
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    Dave already posted the answer.

  4. #4
    ex-DECcie
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    Quote Originally Posted by Hoser83
    that's what I thought too. this is actually a multiple choice assignment, and the the choices I were given are:

    a+2
    a[3]
    a+3
    $(a+2)

    do any of these make sense to you?

    I think Dave pegged it as the first choice there.

    The second choice looks like valid C, but is referencing the 4th element of the array, as array indexes (indices???) always start at 0.

    The third choice is also valid C, but again, references the 4th element.

    The last choice is not valid C.

  5. #5
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    oh, sorry guys. my bad. I didn't know if the

    experssion needed the ptr = a + 2 or if it was just a + 2.
    I got ya now.

    Thanks a lot for the help. I really appreciate it.

  6. #6
    chococoder
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    the expression to reference the 3rd element is "a+2", if you then want to assign that to "ptr" you will need to type "ptr=a+2".

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