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BST memory leak

NightHawk22 (2)
I have been writing and debugging the code for a binary search tree. I have finished it to the specifications, and according to my test driver, it works fine. By running it with Valgrind on a Linux machine, I have found and resolved several memory leaks. But, I have not been able to find the source of the last few. I am new to C++, so I still don't know the ins and outs of pointers. I was wondering if somebody could help me find the last few sources of the memory leaks in my code?

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/*
BST::BST(void) 
{
	size = 0;
	root = 0;
}
	
BST::~BST(void)
{
	while (size != 0)
		remove(root->data);
}

NodeInterface * BST::getRootNode()
{
	return root;
}
	
bool BST::add(int data_in)
{
	bool added = 0;
 
	if (root == NULL)
	{
		root = new Node(data_in);
		size = 1;
		added = 1;
	}	
	else	
		added = add(root, data_in);

	return added;
}
	
bool BST::add(Node * current_node, int data_in)
{
	if (data_in < current_node->data)
	{
		if (current_node->leftChild != NULL)
		{
			return add(current_node->leftChild, data_in);
		}
		else
		{
			current_node->leftChild = new Node(data_in);
			current_node->leftChild->parent = current_node;
			++size;
			return 1;
		}
	}
	else if (data_in > current_node->data)
	{
		if (current_node->rightChild != NULL)
		{
			return add(current_node->rightChild, data_in);
		}
		else
		{
			current_node->rightChild = new Node(data_in);
			current_node->rightChild->parent = current_node;
			++size;
			return 1;
		}
	}
	else
		return 0;
}

bool BST::remove(int data_in)
{
	bool removed = 0;

	if (size == 1 && root->data == data_in)
	{
		delete root;
		root = NULL;
		size = 0;
		removed = 1;
	}
	else if (size > 1)
		removed = remove(root, data_in);

	return removed;
}

bool BST::remove(Node * current, int data_in)
{
	if (data_in < current->data)
	{
		if (current->leftChild != NULL)
			return remove(current->leftChild, data_in);
		else
			return 0;
	}
	else if (data_in > current->data)
	{
		if (current->rightChild != NULL)
			return remove(current->rightChild, data_in);
		else
			return 0;
	}
	else
	{
		if(current->leftChild != NULL && current->rightChild != NULL)
		{
			Node * replace = findMax(current->leftChild);
			
			//if (current == root && root->leftChild == replace)
			//{
				replace->rightChild = root->rightChild;
				root->rightChild->parent = replace;
				replace->parent = NULL;
				root->leftChild = NULL;
				root->rightChild = NULL;
				delete root;
				root = replace;
			//}
		}
		else if (current->leftChild != NULL && current->rightChild == NULL)
		{
			if (current == root)
			{
				root = current->leftChild;
				root->parent = NULL;
				current->leftChild = NULL;
				delete current;
			}
			else
			{
				current->leftChild->parent = current->parent;
				if (current->parent->leftChild == current)
					current->parent->leftChild = current->leftChild;
				else if (current->parent->rightChild == current)
					current->parent->rightChild = current->leftChild;
				current->leftChild = 0;
				current->parent = 0;
				delete current;
			}
		}
		else if (current->leftChild == NULL && current->rightChild != NULL)
		{
			if (current == root)
			{
				current->rightChild->parent = 0;
				root = current->rightChild;
				current->rightChild = 0;
				delete current;
			}
			else
			{
				current->rightChild->parent = current->parent;
				if (current->parent->rightChild == current)
					current->parent->rightChild = current->rightChild;
				else if (current->parent->leftChild == current)
					current->parent->leftChild = current->rightChild;
				current->rightChild = 0;
				current->parent = 0;
				delete current;
			}
		}
		else
		{
			current = current->parent;
			
			if (current->leftChild != NULL && current->leftChild->data == data_in)
			{
				Node * temp = current->leftChild;
				current->leftChild = 0;
				temp->parent = 0;
				delete temp;
			}
			else if (current->rightChild != NULL && current->rightChild->data == data_in)
			{
				Node * temp = current->rightChild;
				current->rightChild = 0;
				temp->parent = 0;
				delete temp;
			}
		}
		--size;
		return 1;
	}
}

Node * BST::findMax(Node * current_node)
{
	while (current_node->rightChild != NULL)
		current_node = current_node->rightChild;
	return current_node;
}
*/

Last edited on
Peter87 (11178)
p.s. Sorry, the formatting was removed upon posting.

That's what the code-tag is for. [code] /* code here */ [/code]
Last edited on
NightHawk22 (2)
Thanks - formatting fixed.
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