void balanceAvl(struct node **root){
if(*root == NULL)
return;
int height_diff = 0;
height_diff = height_difference(*root);
if((*root)->lptr)
balanceAvl(&(*root)->lptr);
else
balanceAvl(&(*root)->rptr);
if(height_diff >= 2){
if(height_difference((*root)->lptr) >= 1)
*root = leftLeftRotate(*root);
else
*root = leftRightRotate(*root);
} else if(height_diff <= -2){
if(height_difference((*root)->rptr) <= -1)
*root = rightRightRotate(*root);
else
*root = rightLeftRotate(*root);
} else{
*root = *root;
}
}
void AVL<T,V>::insert(T Key, V Value){
// I created a new node to add to the AVL tree
// and populated it with the Key/Value pair
TreeNode<T,V>* newNode = new TreeNode<T,V>;
TreeNode<T,V>* parentNode;
newNode->left = NULL;
newNode->right = NULL;
newNode->key = Key;
newNode->value = Value;
parentNode = NULL;
if (root == NULL) // If the AVL tree is empty, create a new start node.
root = newNode;
else // Otherwise, run through the tree and add it to the appropriate end.
{
TreeNode<T,V>* currentNode;
currentNode = root;
while(currentNode != NULL) // While the end of the AVL tree hasn't been reached
{
parentNode = currentNode;
if (newNode->key < currentNode->key) // If the key being added is less then the current key, go left
currentNode = currentNode->left; // Then set the current node to the next left node
else // Otherwise go Right
currentNode = currentNode->right;
}
if (newNode->key < parentNode->key) // Once the end is reached,
{
parentNode->left = newNode; // if the new key is less then it's parents key add it to the left
if(height(root->left) - height(root->right) > 1) // if the height of the left side is greater then 1
{
if(height(root->left->right) - height(root->left->left) > 1)
leftLeftRotate(root); // do either the left right case
else
leftRotate(root); // or the left-left case
}
}
else
{
parentNode->right = newNode;
if(height(root->right) - height(root->left) > 1)
{
if(height(root->right->left) - height(root->right->right) > 1)
rightRightRotate(root);
else
rightRotate(root);
}
}
// I used this to make sure the tree was properly balanced
// When included the height of both the right and left sides of the AVL tree were 30
// std::cout << height(root->left) << ", " << height(root->right) << std::endl;
}
}
