Thread: shuffle 2-dimensional array

Hi,

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

Code:

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;
	}
    }
}

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:

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

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

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