THMMY.gr

// 3) Using pointer to a pointer
// We can create an array of pointers also dynamically using a double pointer. Once we have an array pointers allocated dynamically, we can // dynamically allocate memory and for every row like method 2.

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
    int r = 3, c = 4, i, j, count;
 
    int **arr = (int **)malloc(r * sizeof(int *));
    for (i=0; i<r; i++)
         arr[i] = (int *)malloc(c * sizeof(int));
 
    // Note that arr[i][j] is same as *(*(arr+i)+j)
    count = 0;
    for (i = 0; i <  r; i++)
      for (j = 0; j < c; j++)
         arr[i][j] = ++count;  // OR *(*(arr+i)+j) = ++count
 
    for (i = 0; i <  r; i++)
      for (j = 0; j < c; j++)
         printf("%d ", arr[i][j]);
 
   /* Code for further processing and free the 
      dynamically allocated memory */
 
   return 0;
}

Output:

1 2 3 4 5 6 7 8 9 10 11 12