RBNode <T> MoveRedRight(RBNode <T> node)
{
node.ColorFlip();
if (IsNodeRed(node.LeftChild.LeftChild))
{
node = node.RotateRight();
node.ColorFlip();
}
return(node);
}
RBNode <T> Fixup(RBNode <T> node)
{
if (!IsNodeRed(node.LeftChild) && IsNodeRed(node.RightChild))
{
node = node.RotateLeft();
}
if (IsNodeRed(node.LeftChild) && IsNodeRed(node.LeftChild.LeftChild))
{
node = node.RotateRight();
}
if (IsNodeRed(node.LeftChild) && IsNodeRed(node.RightChild))
{
node.ColorFlip();
}
return(node);
}
// invariant: node is red, or one if its children is red
// As we move down the tree this is preserved by calling MoveRedLeft or
// MoveRedRight, to "borrow red-ness" from a sibling.
protected RBNode <T> DeleteNode(RBNode <T> parent, RBNode <T> node, int index)
{
if (index < node.LeftSize || (index == node.LeftSize && node.Size > 0))
{
if (!IsNodeRed(node.LeftChild) && !IsNodeRed(node.LeftChild.LeftChild))
{
node = MoveRedLeft(node);
}
node.LeftChild = DeleteNode(node, node.LeftChild, index);
}
else
{
bool deleteHere = (index == node.LeftSize);
Debug.Assert(!deleteHere || node.Size == 0, "DeleteNode: Deleted node should be empty");
if (IsNodeRed(node.LeftChild))
{
node = node.RotateRight();
deleteHere = false;
}
if (deleteHere && node.RightChild == null)
{
return(null);
}
if (!IsNodeRed(node.RightChild) && !IsNodeRed(node.RightChild.LeftChild))
{
RBNode <T> temp = node;
node = MoveRedRight(node);
deleteHere = deleteHere && (temp == node);
}
if (deleteHere)
{
RBNode <T> sub;
node.RightChild = DeleteLeftmost(node.RightChild, out sub);
node = Substitute(node, sub, parent);
}
else
{
node.RightChild = DeleteNode(node, node.RightChild, index - node.LeftSize - node.Size);
}
}
return(Fixup(node));
}
// Token: 0x0600769A RID: 30362 RVA: 0x0021E528 File Offset: 0x0021C728
protected RBNode <T> DeleteNode(RBNode <T> parent, RBNode <T> node, int index)
{
if (index < node.LeftSize || (index == node.LeftSize && node.Size > 0))
{
if (!this.IsNodeRed(node.LeftChild) && !this.IsNodeRed(node.LeftChild.LeftChild))
{
node = this.MoveRedLeft(node);
}
node.LeftChild = this.DeleteNode(node, node.LeftChild, index);
}
else
{
bool flag = index == node.LeftSize;
if (this.IsNodeRed(node.LeftChild))
{
node = node.RotateRight();
flag = false;
}
if (flag && node.RightChild == null)
{
return(null);
}
if (!this.IsNodeRed(node.RightChild) && !this.IsNodeRed(node.RightChild.LeftChild))
{
RBNode <T> rbnode = node;
node = this.MoveRedRight(node);
flag = (flag && rbnode == node);
}
if (flag)
{
RBNode <T> sub;
node.RightChild = this.DeleteLeftmost(node.RightChild, out sub);
node = this.Substitute(node, sub, parent);
}
else
{
node.RightChild = this.DeleteNode(node, node.RightChild, index - node.LeftSize - node.Size);
}
}
return(this.Fixup(node));
}
