void findPredecessor(Node** predecessor, Node** parent)
{
	//profiler.countOperation(nrOfOperations[0], sizeCount, 1);
	//if (*predecessor == NULL)
		//return;

	(*parent)->size--;
	while ((*predecessor)->right != NULL)
	{
		profiler.countOperation(nrOfOperations[0], sizeCount, 3);
		*parent = *predecessor;
		(*parent)->size--;
		*predecessor = (*predecessor)->right;
	}
	profiler.countOperation(nrOfOperations[0], sizeCount, 1);
}

Node* osDelete(Node* root, int rank)
{
	if (root == NULL) //rank too big
		return root;
	int rankOfRoot;

	//profiler.countOperation(nrOfOperations[1], sizeCount, 1);
	if (root->left == NULL)
		rankOfRoot = 1;
	else
		rankOfRoot = root->left->size + 1;


		if (rank < rankOfRoot)
		{
			root->left = osDelete(root->left, rank);
			root->size--;
			return root;
		}
		else
			if (rank > rankOfRoot)
			{
				root->right = osDelete(root->right, rank - rankOfRoot);
				root->size--;
				return root;
			}
			else // node with needed rank found
			{
				if(root->left == NULL)
					if (root->right == NULL) //leaf
					{
						free(root);
						return NULL;
					}
					else //single child to the right
					{
						root->size--;
						Node* aux = root->right;
						free(root);
						return aux;
					}
				else // we have child on left
					if (root->right == NULL) // single child to the left
					{
						root->size--;
						Node* aux = root->left;
						free(root);
						return aux;
					}
					else // 2 children.
					{

						Node* predecessor = root->left;
						Node* parent = root;
						//in findPredecessor we update the size field
						findPredecessor(&predecessor, &parent);
						//printf("predecessor is %d, parent is %d\n", predecessor->key, parent->key);
						root->key = predecessor->key;
						if (parent == root)
						{
							root->key = predecessor->key;
							root->left = predecessor->left;
							free(predecessor);
						}
						else
						{
							root->key = predecessor->key;
							parent->right = predecessor->left;
							free(predecessor);
						}
						return root;
					}
			}

}