shuffle 2-dimensional array

Hi,

I found this code for shuffle one-dimensional int array somewhere:

Code:

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void shuffle(int *array, size_t n)
{
    if (n > 1) {
        size_t i;
        for (i = 0; i < n - 1; i++) {
          size_t j = i + rand() / (RAND_MAX / (n - i) + 1);
          int t = array[j];
          array[j] = array[i];
          array[i] = t;
        }
    }
}

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How can I make change to this function to shuffle 2-dimensional array. This is the declaration of the 2-dimensional array I need to shuffle.

Code:

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char list[2000][20];

---

This array is an array of string (20 char max). I need to shuffle the outer array not the inner one.

Any help would be really appreciated,
Pat

So have a temporary 20 char string and use strcpy to the swap.

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Mats

3rd forum I've seen this on - spamalot?

What do you mean when you say need to shuffle the outer array not the inner one.

Quote:

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Originally Posted by itCbitC

What do you mean when you say need to shuffle the outer array not the inner one.

---

From this:

Code:

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char arr[3][10] = { "Hello", "New", "World" };

shuffle(arr);

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we want something like "New", "World", "Hello" in the array, not "eNl", "Hwldo" ,"Wrdll" [I'm not sure that's actually not lost or gained some letters, but I think it gets the message across].

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Mats

Well thanks for the great explanation matsp, I thought it is the exact opposite where the columns of each row are shuffled around.