public void Insert(T key)
{
var parent = _SentryNode;
var current = _Root;
while (current != _SentryNode)
{
parent = current;
if (current.Value.CompareTo(key) > 0)
{
current = current.Left;
}
else
{
current = current.Right;
}
}
var node = new RBTreeNode <T>(key);
node.Parent = parent;
if (parent == _SentryNode)
{
_Root = node;
}
else
{
if (parent.Value.CompareTo(key) > 0)
{
parent.Left = node;
}
else
{
parent.Right = node;
}
}
node.Left = _SentryNode;
node.Right = _SentryNode;
node.Color = RBColor.RED;
RBInsertFixUp(node);
}
public RBTreeNode <T> Predecessor(RBTreeNode <T> node)
{
if (node == null)
{
throw new ArgumentNullException();
}
if (node.Left != _SentryNode)
{
return(_Maximum(node.Left));
}
var current = node;
var parent = node.Parent;
while (parent != _SentryNode && parent.Left == current)
{
current = parent;
parent = parent.Parent;
}
return(parent);
}
public RBTreeNode <T> Successor(RBTreeNode <T> node)
{
if (node == null)
{
throw new ArgumentNullException();
}
if (node.Right != _SentryNode)
{
return(_Minimum(node.Right));
}
var current = node;
var parent = current.Parent;
while (parent != _SentryNode && parent.Right == current)
{
current = parent;
parent = parent.Parent;
}
return(parent);
}
public RedBlackTree()
{
_SentryNode = new RBTreeNode <T>(RBColor.BLACK);
_Root = _SentryNode;
}
private void RBDeleteFixUp(RBTreeNode <T> fixNode)
{
var node = fixNode;
while (node != _SentryNode && node.Color == RBColor.BLACK)
{
if (node == node.Parent.Left)
{
var right = node.Parent.Right;
if (right.Color == RBColor.RED)
{
right.Color = RBColor.BLACK;
node.Parent.Color = RBColor.RED;
LeftRotate(node.Parent);
right = node.Parent.Right;
}
if (right.Left.Color == RBColor.BLACK && right.Right.Color == RBColor.BLACK)
{
right.Color = RBColor.RED;
node = node.Parent;
}
else if (right.Right.Color == RBColor.BLACK)
{
right.Left.Color = RBColor.BLACK;
right.Color = RBColor.RED;
RightRotate(right);
right = node.Parent.Right;
}
right.Color = node.Parent.Color;
node.Parent.Color = RBColor.BLACK;
right.Right.Color = RBColor.BLACK;
LeftRotate(node.Parent);
node = _Root;
}
else
{
var left = node.Parent.Left;
if (left.Color == RBColor.RED)
{
left.Color = RBColor.BLACK;
node.Parent.Color = RBColor.RED;
RightRotate(node.Parent);
left = node.Parent.Left;
}
if (left.Left.Color == RBColor.BLACK && left.Right.Color == RBColor.BLACK)
{
left.Color = RBColor.RED;
node = node.Parent;
}
else if (left.Left.Color == RBColor.BLACK)
{
left.Right.Color = RBColor.BLACK;
left.Color = RBColor.RED;
LeftRotate(left);
left = node.Parent.Left;
}
left.Color = node.Parent.Color;
node.Parent.Color = RBColor.BLACK;
left.Left.Color = RBColor.BLACK;
RightRotate(node.Parent);
node = _Root;
}
}
node.Color = RBColor.BLACK;
}
public RedBlackTree(IEnumerable <T> collections)
{
_SentryNode = new RBTreeNode <T>(RBColor.BLACK);
_Root = _SentryNode;
Build(collections);
}
