Change array length

This is a discussion on Change array length within the C Programming forums, part of the General Programming Boards category; On beginning I define two arrays a[5]; b[5]; after this I need next array C c[5]; but when I have ...

  1. #1
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    Change array length

    On beginning I define two arrays

    a[5];
    b[5];

    after this I need next array C

    c[5];

    but when I have c[5] = a[5] + b[5]

    I have overflow of array C.

    how can I change length of array C in loop, I don't change C if I don't have overflow

  2. #2
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    It would be c[4] = a[4] + b[4].

  3. #3
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    Remember that arrays in C begin with index 0, so array[5] gives you indeces 0-4 only.

  4. #4
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    I know that a[0] is first element of array

    I have need for something like this:
    Code:
    a[5] = {9,9,9,9,9,9}
    +
    b[5] = {8,8,8,8,8,8}
    =
    c[5+1] = {1,8,8,8,8,8,7}
    that mean c[i+1] = a[i] + b[i]
    but 1 in [i+1] is conditioned by add, it not always present
    Code:
    a[5] = {4,4,4,4,4,4}
    +
    b[5] = {4,4,4,4,4,4};
    =
    c[5] = {8,8,8,8,8,8};
    in this case I don't have need for +1 in c[i]

  5. #5
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    Set the length of array c to be 6 and, in cases where the length of the result is 5, make the first element zero.
    Right 98% of the time, and don't care about the other 3%.

    If I seem grumpy or unhelpful in reply to you, or tell you you need to demonstrate more effort before you can expect help, it is likely you deserve it. Suck it up, Sunshine, and read this, this, and this before posting again.

  6. #6
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    define array c longer length.
    Code:
    int c[255] = {0};
    then when you do " a[5] = {4,4,4,4,4,4}+b[5] = {4,4,4,4,4,4};"
    the result put into c can be begin from 0,
    like c[0] = a[4]+b[4],c[1] = a[3]+b[3]...
    Last edited by Jesius; 11-28-2010 at 03:34 AM.

  7. #7
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    Quote Originally Posted by miroslavgojic View Post
    On beginning I define two arrays

    a[5];
    b[5];

    after this I need next array C

    c[5];

    but when I have c[5] = a[5] + b[5]

    I have overflow of array C.

    how can I change length of array C in loop, I don't change C if I don't have overflow
    Are you sure you're not tripping over that old C problem where the number of elements does not equal the numbers of the elements?

    Array elements always number from 0, not from 1, so a[5] has elements numbered 0 ,1 ,2, 3, 4

    There is no element #5... but there is The 5th Element

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