NodeAVL <T> rotateLeft(NodeAVL <T> node) // левый поворот вокруг node
{
NodeAVL <T> newNode = node.right;
if (node.Equals(root))
{
newNode.parent = null;
root = newNode;
}
else
{
if (isLeft(node))
{
node.parent.left = newNode;
}
else
{
node.parent.right = newNode;
}
}
node.right = newNode.left;
newNode.left = node;
newNode.parent = node.parent;
node.parent = newNode;
fixHeight(node);
fixHeight(newNode);
return(newNode);
}
public NodeAVL <T> insert(T key)//вставка элемента
{
NodeAVL <T> node = (NodeAVL <T>)root;
insert(key, node);
return(node);
}
public NodeAVL(T val, NodeAVL <T> par = null)
{
this.key = val;
this.height = 1;
this.parent = par;
this.left = null;
this.right = null;
}
private NodeAVL <T> insert(T key, NodeAVL <T> node, NodeAVL <T> parent = null)
{
if (node == null)
{
node = new NodeAVL <T>(key, parent);
}
else if (key.CompareTo(node.key) < 0)
{
balance(node.left = insert(key, (NodeAVL <T>)node.left, node));
}
else
{
balance(node.right = insert(key, (NodeAVL <T>)node.right, node));
}
return(node);
}
NodeAVL <T> balance(NodeAVL <T> node) // балансировка узла
{
fixHeight(node);
if (balanceFactor(node) == 2)
{
if (balanceFactor(node.right) < 0)
{
rotateRight(node.right);
}
rotateLeft(node);
}
else if (balanceFactor(node) == -2)
{
if (balanceFactor(node.left) > 0)
{
node.left = rotateLeft(node.left);
}
rotateRight(node);
}
return(node);
}
private void fixHeight(NodeAVL <T> node)
{
node.height = (height(node.left) > height(node.right) ? height(node.left) : height(node.right)) + 1;
}
private int balanceFactor(NodeAVL <T> node)
{
return(height(node.right) - height(node.left));
}
private int height(NodeAVL <T> node)
{
return(node != null ? node.height : 0);
}
public AVLTree(T val)
{
root = new NodeAVL <T>(val);
}