[A89] Re: Multi-dimensional Arrays in C...

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[A89] Re: Multi-dimensional Arrays in C...

>Any suggestions?

I've attached a sample program demonstrating dynamic multi-dimensional
array allocation (works fine w/ gcc.) The best way to tackle the situation
is to remember that the concept of "multi-dimensional" arrays is an
abstraction and you can see the mechanics behind it by taking a close look
at what they really are, arrays of pointers.

The way I demonstrate isn't nice and magical, but I'm sure you could write
a function (perhaps using recursion) to dynamically create arrays of any
number of dimensions. MultiDimensionalAlloc() or something like that ;)




-- Attached file included as plaintext by Listar --

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

int **array;


int main()
{
    int i;

    /*
     * Allocate 256 elements of "int *". So, array[] is an array of 256 int *
     * pointers.
     */

    array = calloc(256, sizeof(int *));

    /*
     * Next, allocate memory using each of the 256 int * pointers. I'm only
     * going to allocate one int of space per pointer for this example.
     */

    for (i = 0; i < 256; i++)
    {
        array[i] = calloc(1, sizeof(int));
        *array[i] = i;
    }

    /*
     * In the last for-loop, you will notice that I assigned the current loop
     * counter value to the memory allocated. This next for-loop prints out
     * the values.
     */

    for (i = 0; i < 256; i++)
        printf("%d\n", *array[i]);

    /*
     * Free the memory.
     */

    for (i = 0; i < 256; i++)
        free(array[i]);
    free(array);

    return 0;
}


-- Attached file included as plaintext by Listar --


Bart
References: