The cdds from ryantheinventor

Copy assignment operator should clean up/overwrite existing data

Lines 129 to 138 in 4294dc4

    
           tDoubleLinkList<T> &tDoubleLinkList<T>::operator=(const tDoubleLinkList &rhs) 
        
           { 
        
           	Node *cur = rhs.head; 
        
           	while (cur != NULL) 
        
           	{ 
        
           		push_back(cur->data); 
        
           		cur = cur->next; 
        
           	} 
        
           	return *this; 
        
           }

Since a list being assigned to may already have existing nodes, you should take care to them up first before overwriting the head and tail variable on the list with new nodes duplicated from the other list.

Potential deference of null pointer in binary tree dtor and clear

CDDS/BinaryTree/tBinaryTree.h

Lines 86 to 92 in dc470d1

    
           template<typename T> 
        
           tBinaryTree<T>::~tBinaryTree()  
        
           { 
        
           	//remove all nodes 
        
           	rVertexDel(*root); 
        
           	delete root; 
        
           }

root is initialized to nullptr on construction, which is proper and valid behavior. However, the destructor always deferences root, which can be null if no nodes were added/all nodes were removed.

Deferencing a null pointer is UB; it crashes with MSVC14.

Repro w/ the following code:

#include "tBinaryTree.h"

int main() 
{
	// construct val in a new "scope"
	{
		tBinaryTree<int> val;
	}
	// val will be destroyed before moving past this point

	return 0;
}

Potentially undefined use of NULL

CDDS/CDDS/tDoubleLinkList.h

Lines 12 to 13 in 4294dc4

    
           Node *next = NULL;// pointer to node following this node 
        
           Node *prev = NULL;

Use of NULL is serviceable, but nullptr is preferred for coursework. Additionally, this header alone does not define NULL so use of this may result in compilation errors since NULL may go undefined as a macro or identifier. While nullptr is again preferred, other options include...

defining the NULL macro yourself at the top #define NULL 0
including #include <cstddef> at the top which defines NULL (see cppref)
using nullptr, a keyword providing a pointer literal for a null pointer 😃 (see cppref)

The use of nullptr is preferred in contexts like UE4 and also avoids any problems that may stem from accidentally providing a pointer where a numerical value is expected.

Pre-operators should return references to the iterators being incremented

CDDS/CDDS/tDoubleLinkList.h

Lines 44 to 48 in 4294dc4

    
           iterator operator++() // pre-increment (returns a reference to this iterator after it is incremented) 
        
           { 
        
           	cur = cur->next; 
        
           	return *this; 
        
           }

CDDS/CDDS/tDoubleLinkList.h

Lines 55 to 59 in 4294dc4

    
           iterator operator--() // pre-increment (returns a reference to this iterator after it is incremented) 
        
           { 
        
           	cur = cur->prev; 
        
           	return *this; 
        
           }

The implementations for your pre-inc/pre-dec operators should return references. As they are now, they are only returning copies of themselves.

To make this change, alter the return type of those operators such that they return iterator & where the & denotes that the return type will be a reference rather than a plain value type.

A more idiomatic way of writing !=

CDDS/CDDS/tDoubleLinkList.h

Lines 36 to 39 in 4294dc4

    
           bool operator!=(const iterator &rhs) const// returns false if the iterator does not point to the same node 
        
           { 
        
           	return !operator==(rhs);//No clue if this works 
        
           }

This does work! You may want to rewrite instead as...

return !(*this == rhs);

.. which may be more idiomatic.

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Copy assignment operator should clean up/overwrite existing data

Potential deference of null pointer in binary tree dtor and clear

Potentially undefined use of NULL

Pre-operators should return references to the iterators being incremented

A more idiomatic way of writing !=

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	tDoubleLinkList<T> &tDoubleLinkList<T>::operator=(const tDoubleLinkList &rhs)
	{
	Node *cur = rhs.head;
	while (cur != NULL)
	{
	push_back(cur->data);
	cur = cur->next;
	}
	return *this;
	}

	template<typename T>
	tBinaryTree<T>::~tBinaryTree()
	{
	//remove all nodes
	rVertexDel(*root);
	delete root;
	}

	Node *next = NULL;// pointer to node following this node
	Node *prev = NULL;

	iterator operator++() // pre-increment (returns a reference to this iterator after it is incremented)
	{
	cur = cur->next;
	return *this;
	}

	iterator operator--() // pre-increment (returns a reference to this iterator after it is incremented)
	{
	cur = cur->prev;
	return *this;
	}

	bool operator!=(const iterator &rhs) const// returns false if the iterator does not point to the same node
	{
	return !operator==(rhs);//No clue if this works
	}