Given the following class:

```cpp
class GiftBox {
char* labelName;
double cubeVolume;
double weight;
};
```

Answer the following questions:

1. Create a default no-argument constructor to set `cubeVolume` and `weight` to 0, and `labelName` to an empty string (start with null character '\0').

2. Create a three-argument constructor to set `cubeVolume`, `weight`, and `labelName` to the given argument values. Validate first if the double values are positive and the label name is not `nullptr` and not an empty string '\0' before using it, otherwise do nothing.

3. Define a destructor to deallocate the memory pointed by `labelName`, and print "object of type GiftBox just destroyed."

4. Implement a function called `display` that takes an `ostream` (`std::ostream& display() const;`) to display the information as shown in the sample output.

5. Implement two member operators `+= double` (adds the double value to the weight) and `+= object of the same type` (add the `cubeVolume` and `weight` to the current one; no change for the label).

6. Implement a helper operator `<<` that uses `display` implemented in part 4.

Use the following template for your answer (i.e., copy this text and insert your answers within it):

```cpp
// Name:
// ID:

// Email:

class GiftBox {
char* labelName;
double cubeVolume;
double weight;

// add all declarations that can be added here
// (the fifth one is provided to you)

void display(std::ostream& os) const;
};

// implement your functions here

// Sample tester for your code.
// NO NEED TO HAVE EXACT OUTPUT BASED ON THIS CODE.
// THIS IS TO GIVE YOU AN IDEA OF THE EXPECTED OUTPUT FOR EACH QUESTION ABOVE
int main() {
GiftBox g1, g2(4000.8, 200.2, "Sweet Box"), g3(2000, 100.2, "Box!");

cout << g1;
g2 += 100;
cout << g2;
g2 += g3;
cout << g2;
}

Output:

No data is available in this object.

Sweet Box
==========
cubeVolume=4000.8Cm3 and weight=300.2Grm

Sweet Box
==========
cubeVolume=4000.8Cm3 and weight=400.2Grm

Sweet Box
==========
cubeVolume=6000.8Cm3 and weight=500.4Grm

object of type GiftBox just destroyed

object of type GiftBox just destroyed

object of type GiftBox just destroyed
```