/// <summary>
/// Adds an item to the <see cref="T:System.Collections.Generic.ICollection`1"/>.
/// </summary>
/// <param name="item">The object to add to the <see cref="T:System.Collections.Generic.ICollection`1"/>.</param><exception cref="T:System.NotSupportedException">The <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only.</exception>
public void Add(T item)
{
grandParent = header;
parent = grandParent;
current = parent;
nullNode.Element = item;
while (current.Element.CompareTo(item) != 0)
{
RBNode <T> greatParent = grandParent;
grandParent = parent;
parent = current;
current = item.CompareTo(current.Element) < 0 ? current.Left : current.Right;
if (current.Left.Color == Color.Red && current.Right.Color == Color.Red)
{
HandleReorient(item);
}
}
if (current != nullNode)
{
return;
}
current = new RBNode <T>(item, nullNode, nullNode);
if (item.CompareTo(parent.Element) < 0)
{
parent.Left = current;
}
else
{
parent.Right = current;
}
HandleReorient(item);
}
private RBNode <T> RotateWithLeftChild(RBNode <T> node)
{
var k1 = node.Left;
node.Left = k1.Right;
k1.Right = node;
return(k1);
}
private RBNode <T> RotateWithRightChild(RBNode <T> k1)
{
RBNode <T> k2 = k1.Right;
k1.Right = k2.Left;
k2.Left = k1;
return(k2);
}
///<summary>
///</summary>
///<param name="element"></param>
public RBTree(T element)
{
current = new RBNode <T>();
parent = new RBNode <T>();
grandParent = new RBNode <T>();
greatParent = new RBNode <T>();
nullNode = new RBNode <T>();
nullNode.Left = nullNode;
nullNode.Right = nullNode;
header = new RBNode <T>(element)
{
Left = nullNode, Right = nullNode
};
}
private RBNode <T> Rotate(T item, RBNode <T> Parent)
{
if (item.CompareTo(Parent.Element) < 0)
{
return
(Parent.Left =
item.CompareTo(Parent.Left.Element) < 0
? RotateWithLeftChild(Parent.Left)
: RotateWithRightChild(Parent.Left));
}
return
(Parent.Right =
item.CompareTo(Parent.Right.Element) < 0
? RotateWithLeftChild(Parent.Right)
: RotateWithRightChild(Parent.Right));
}
private IEnumerable <ItemColor <T> > InOrden(RBNode <T> Current)
{
if (Current.Left != null)
{
InOrden(Current.Left);
}
yield return(new ItemColor <T> {
Element = Current.Element, Color = Current.Color
});
if (Current.Right != null)
{
InOrden(Current.Right);
}
}
private void HandleReorient(T item)
{
current.Color = Color.Red;
current.Left.Color = Color.Black;
current.Right.Color = Color.Black;
if (parent.Color == Color.Red)
{
grandParent.Color = Color.Red;
int x_1 = item.CompareTo(grandParent.Element);
int x_2 = item.CompareTo(parent.Element);
if (x_1 < 0 && x_1 != x_2)
{
current = Rotate(item, grandParent);
current.Color = Color.Black;
}
header.Right.Color = Color.Black;
}
}
