dynamic array please!

[acorea20]

I need help fixing the array of pointers I created. When I try to insert more than one element the program crashes. The function where the array of pointers is created calls another function to then sort the array of pointers in order.

  	CDNode<KEY, VALUE>* maintain(CDNode<KEY, VALUE>* subtree) {
		subtree->decrease_timer();
		if (subtree->timer() > 0) {
			return subtree;
		}
		else {
			int k = 0;
			k = tree_size(subtree);
			CDNode<KEY, VALUE> **array;
			array = new CDNode<KEY, VALUE>*[k];
			for (int i = 0; i < k; i++) {
				array[tree_to_array(array, 0, subtree)] = NULL;
			}
			subtree = array_to_tree(array, 0, k);
			for (int j = 0; j < k; j++) {
				delete array[j];
			}
			delete[] array;
			return subtree;
		}
	}

	int tree_size(CDNode<KEY, VALUE>* subtree) {
		if (NULL == subtree)
		{
			return 0;
		}
		else
			return tree_size(subtree->left()) + 1 + tree_size(subtree->right());
	}

	int tree_to_array(CDNode<KEY, VALUE> **array_of_pointers, int start_index, CDNode<KEY, VALUE>* subtree) {
		if (NULL == subtree) {
			return start_index;
		}
		else {
			start_index = tree_to_array(array_of_pointers, start_index, subtree->left());
			array_of_pointers[start_index] = subtree;
		}
		return tree_to_array(array_of_pointers, start_index + 1, subtree->right());
	}

	CDNode<KEY, VALUE>* array_to_tree(CDNode<KEY, VALUE> **array_of_pointers, int start_index, int end_index) {
		int NUM_OF_NODES = (end_index - start_index);
		if (NUM_OF_NODES == 0) {
			return NULL;
		}
		else {
			int middle = (start_index + end_index) / 2;
			_root = array_of_pointers[middle];
			_root->set_left(array_to_tree(array_of_pointers, start_index, middle));
			_root->set_right(array_to_tree(array_of_pointers, middle + 1, end_index));
			if (NUM_OF_NODES >= 3) {
				int result = 0;
				result = 1 + ((NUM_OF_NODES - 1) / 3);
				_root->set_timer(result);
			}
			else {
				_root->set_timer(1);
			}
		}
		return _root;
	}

[cire]

What is tree_to_array supposed to do? What is its return value supposed to be?

Can you explain in general terms what you're trying to accomplish?

[acorea20]

tree_to_array is supposed to initialize the array of node pointers with all the nodes of a subtree in order.

I'm trying to create kind of a mixture between a BST and an AVL tree. Where each node has a timer that keeps track of how “worn out” the node is, meaning it is decremented each time a node is inserted. When the timer reaches zero--starting from 1--the node is due for maintenance, so its subtree is ripped apart and rebuilt as a perfect binary subtree.

[cire]

So, tree_to_array is supposed to fill an array with pointers to existing nodes and return the number of the pointers that have been added to the array?

The first thing that pops out to me is the difference between lines 37 and 40 with respect to the index being passed to the function.

The second is: Why is there a loop beginning on line 11?

The third is: Line 12 will exceed the bounds of the array, resulting in undefined behavior.

[acorea20]

tree_to_array returns the next index that needs to be initialized and since zero is first index passed, then it in increments it by adding that one the next time it passed.
I wasn't really sure how to go about creating the array of node pointers so I did that loop to initialize the new array of pointers I created.