#include <stdio.h>
#include <stdlib.h>
int main()
{
int i; /* general purpose variable used for loop index */
int j; /* general purpose variable used for loop index */
int **a; /* this is the array name */
int size_x; /* this variable will be used for the
first dimension */
int size_y; /* this variable will be used for the
second dimension */
/* suppose we want an array of int:
a[5][3] */
size_x = 5;
size_y = 3;
/*
allocate storage for an array of pointers */
a = malloc(size_x * sizeof(int *));
/* for each pointer, allocate storage
for an array of ints */
for (i = 0; i < size_x; i++) {
a[i] = malloc(size_y * sizeof(int));
}
/* just for kicks, show the addresses
(note: not all sequential) */
/* assign an arbitrary value to each
element */
for (i = 0; i < size_x; i++) {
for (j = 0; j < size_y; j++) {
printf("&a[%d][%d]
= %p\n", i, j,
&a[i][j]); /*
show the addresses */
a[i][j] = i * size_y + j; /* just some unique number for each element */
}
printf ("\n");
}
/* now show the contents that were
assigned */
for (i = 0; i < size_x; i++) {
for (j = 0; j < size_y; j++) {
printf("a[%d][%d]
= %2d\n", i,
j, a[i][j]);
}
printf ("\n");
}
/* now for each pointer, free its
array of ints */
for (i = 0; i < size_y; i++) {
free(a[i]);
}
/* now free the array of pointers */
free(a);
return 0;
}
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