memcpy(new_array, * ptr_old_array, old_size);
memcpy(new_array + (old_n * region_size), new_region, region_size);
free(* ptr_old_array);
memcpy(new_array, * ptr_old_array, old_size);
memcpy(new_array + (old_n * region_size), new_region, region_size);
free(* ptr_old_array);