AVL insertAVL(AVLType n, AVL node) {
AVL root = node;
List path;
while(node) {
path = cons(node, path);
if(n < node->element) node = node->left;
else if(n > node->element) node = node->right;
else if(n == node->element) return root;
}
node = constructAVL(n); /* construct a node containing n at this null position */
/* Now we can move back up, testing heights and rotating imbalances */
while(path) {
node = path->element;
current->height = max(height(node->left) - height(node->right))+1;
/* Where height of NULL is -1, height of leaves is 0, etc */
AVL parent;
if(height(node->left) - height(node->right) == 2) {
if(n < node->left->element) rotated = s_rotate_left(node);
else rotated = d_rotate_right(node);
parent = path->next->element
if(parent->left == node) parent->left = rotated;
else parent->right = rotated;
}
/* Then we do the same as above except where the height difference is -2
* and the rotations go right */
path = path->next;
}
return node; /* This will be the root and the last element of path (possibly
a different root than the original due to rotations) */
}
avl_ptr d_rotate_right(avl_ptr k3)
{
k3->right=s_rotate_left(k3->right);
return(s_rotate_right(k3));
}
