private IntBBSTNode ReBalance(IntBBSTNode node)
{
var balanceFactor = BalanceFactor(node);
if (balanceFactor > 1)
{
if (BalanceFactor(node.left) > 0)
{
node = LeftLeft_Rotation(node);
}
else
{
node = LeftRight_Rotation(node);
}
}
else if (balanceFactor < -1)
{
if (BalanceFactor(node.right) > 0)
{
node = RightLeft_Rotation(node);
}
else
{
node = RightRight_Rotation(node);
}
}
return(node);
}
private IntBBSTNode RightLeft_Rotation(IntBBSTNode parent)
{
IntBBSTNode temp = parent.right;
parent.right = LeftLeft_Rotation(temp);
return(RightRight_Rotation(parent));
}
private IntBBSTNode LeftRight_Rotation(IntBBSTNode parent)
{
IntBBSTNode temp = parent.left;
parent.left = RightRight_Rotation(temp);
return(LeftLeft_Rotation(parent));
}
protected int BalanceFactor(IntBBSTNode node)
{
if (node == null)
{
return(0);
}
return(Depth(node.left) - Depth(node.right));
}
protected int Depth(IntBBSTNode node)
{
if (node == null)
{
return(0);
}
return(Math.Max(Depth(node.left), Depth(node.right)) + 1);
}
public void Add(int ele)
{
if (root_ == null)
{
root_ = new IntBBSTNode(ele);
return;
}
root_ = Insert(root_, ele);
}
/// <summary>
/// A B
/// / \ / \
/// X B ---> A C
/// / \ / \ \
/// Y C X Y N
/// N
/// </summary>
/// <param name="parent">A</param>
/// <returns></returns>
private IntBBSTNode RightRight_Rotation(IntBBSTNode parent)
{
IntBBSTNode temp;
temp = parent.right;
parent.right = temp.left;
temp.left = parent;
return(temp);
}
private void Inorder(IntBBSTNode root, System.Action <IntBBSTNode> func)
{
if (root == null)
{
return;
}
Inorder(root.left, func);
func.Invoke(root);
Inorder(root.right, func);
}
private IntBBSTNode Insert(IntBBSTNode root, int value)
{
if (root == null)
{
root = new IntBBSTNode(value);
return(root);
}
else if (value < root.key)
{
root.left = Insert(root.left, value);
root = ReBalance(root);
}
else if (value >= root.key)
{
root.right = Insert(root.right, value);
root = ReBalance(root);
}
return(root);
}
public IntBBSTNode(int ele, IntBBSTNode left, IntBBSTNode right)
{
this.key = ele; this.left = left; this.right = right;
}
public IntBBSTNode()
{
this.left = this.right = null;
}
public IntBBST()
{
this.root_ = null;
}
