Question

I have a Binary Search Tree, I use template to add any class object to it.

I have a search function that returns said class object or NULL

Do I need to overload “=” to return this object ? I was hoping if I return object it would know to check: If same type replace values stored in LHS with values stored in RHS and if NULL mark first object as NULL.

Is my mistake maybe somewhere else (all I return is either full object or NULL, nothing else) or do I actually have to overload it ?

I have limited time (very) so how can I do this if needed ? and is it a fast process or will it involve a lot of modifications.

Sorry for lack of code but I can’t think of any that would be relevant.

EDIT I also use a lot of NULL so can I return NULL into an object ? Example:

class Matrix {
   private:
     int col;
     int line;
     int value;
}

Matrix mat; mat = NULL;

Some code:

template <typename Type>
Type BST<Type>::search(int key) {
    if (this->root == NULL)
        return NULL;
    else
        return root->search(key);

Here Type is Matrix. Can I return NULL or go further with search and return Type, which again is Matrix?

Note: This is for homework purposes, leaking memory is my last concern. Simplicity and speed is by far my first problem

Answer 1

No, you cannot assign NULL to an object.

Matrix mat; mat = NULL;

Is illegal in your case. If you want to be able to have NULL, you can use pointers instead (raw or smart).