private void updateHeight(AVLTreeNode<E> node) {
if (node.left == null && node.right == null) node.height = 0;
else if (node.left == null) node.height = 1 + ((AVLTreeNode<E>) (node.right)).height;
else if (node.right == null) node.height = 1 + ((AVLTreeNode<E>) (node.left)).height;
else
node.height =
1
+ Math.max(
((AVLTreeNode<E>) (node.right)).height, ((AVLTreeNode<E>) (node.left)).height);
}
// RR rotation
private void rotateRR() {
AVLTreeNode Me = this;
AVLTreeNode Left = this.LeftNode;
// switch 'Me' and 'Left' and attach 'Me' to the right connector of 'Left'
if (Me.Parent != null) Me.Parent.updateMyConnector(Me, Left);
Left.Parent = Me.Parent;
if (Left.Parent == null) this.tree.root = Left;
Me.Parent = Left;
Me.LeftNode = null;
if (Left.RightNode != null) {
// we need to drop a node attached to the place where 'Me' is going to be attached
// so we don't lose it. We're going to attach it to 'Me' instead
//
// Before: Element attached to 'Left'
// Going to be: Element attached to 'Me' which is attached to 'Left'
// print("[DEBUG] Dropping right node " + Left.RightNode.Name + " caught by " + Me.Name)
Left.RightNode.Parent = Me;
Me.LeftNode = Left.RightNode;
}
// finally attach 'Me'
Left.RightNode = Me;
}
/** @param value */
@Override
public void add(V value) {
if (root_node == null) {
root_node = new AVLTreeNode(null, value);
} else {
((AVLTreeNode) root_node).add(value);
// make sure its still root
while (root_node.getParentNode() != null) {
root_node = root_node.getParentNode();
}
}
}
// LL rotation (same as for RR but mirrored)
private void rotateLL() {
AVLTreeNode Me = this;
AVLTreeNode Right = this.RightNode;
if (Me.Parent != null) Me.Parent.updateMyConnector(Me, Right);
Right.Parent = Me.Parent;
if (Right.Parent == null) this.tree.root = Right;
Me.Parent = Right;
Me.RightNode = null;
if (Right.LeftNode != null) {
// print("[DEBUG] Dropping left node " + Right.LeftNode.Name + " caught by " + Me.Name)
Right.LeftNode.Parent = Me;
Me.RightNode = Right.LeftNode;
}
Right.LeftNode = Me;
}
private AVLTreeNode singleRotateRight(AVLTreeNode node) {
AVLTreeNode parent_node = (AVLTreeNode) node.getParentNode();
AVLTreeNode swap_node = (AVLTreeNode) node.getRightChild();
node.setRightChild(swap_node.getLeftChild());
swap_node.setLeftChild(node);
node.setDepth(max(node.getLeftChildDepth(), (node.getRightChildDepth() + 1)));
swap_node.setDepth(max(swap_node.getRightChildDepth(), (node.getDepth() + 1)));
if (parent_node == null) {
swap_node.setParentNode(parent_node);
} else {
if (parent_node.getLeftChild() == node) {
parent_node.setLeftChild(swap_node);
} else {
parent_node.setRightChild(swap_node);
}
}
return swap_node;
}
private AVLTreeNode doubleRotateLeft(AVLTreeNode node) {
node.setLeftChild(singleRotateRight((AVLTreeNode) node.getLeftChild()));
return singleRotateLeft(node);
}
