void add_num(int num)
{
	num += 1;
}

void add_num_ptr(int* num)
{
	*num += 1;
}

int main(void)
{
	int number = 12;
	printf("%d\n", add_num); // prints 12
	printf("%d\n", add_num); // prints 12
	printf("%d\n", add_num_ptr(&num)); // prints 13
	printf("%d\n", add_num_ptr(&num)); // prints 14
}