/* Example taken from  http://www.ihypress.net/programming/c/prog.php?chap=09&pgm=05
Dynamic allocation of a 2D array */
/* (Software Engineer's Method) */

#include <stdio.h>
#include <stdlib.h>

/* Dynamic allocation of arrays of more than one dimension is easily done. 
You can simulate a two-dimensional array with a single, dynamically-allocated 
one-dimensional array. However, you must now perform subscript calculations 
manually, accessing the [i][j]th element with array[i * ncolumns + j]. 
Software engineers prefer this method for its elegance and efficiency */

int main (void)
{
	int nrows, ncols, i, j;
	int *numbers; /* pointer to the first cell ([0]) */
	
	printf ("How many rows and columns?> ");
	scanf ("%d%d", &nrows, &ncols);

	/* allocating the array of integers */
	numbers = (int *) calloc (nrows*ncols, sizeof(int));

	i=1; j=1;
	numbers[i*ncols+j] = 9; /* initializes one value to 9 */
	
	
	for (i=0; i<nrows; i=i+1)
	{	
		for (j=0; j<ncols; j=j+1)
		{
			printf ("%3d ", numbers[i*ncols+j]);
			
		}
		printf ("\n");
	}


	free (numbers);
	return (0);
}