private void RemoveNode(IntervalNode <TKey, TValue> node)
{
if (node == Sentinel)
{
return;
}
IntervalNode <TKey, TValue> temp = node;
if (node.Right != Sentinel && node.Left != Sentinel)
{
// Trick when deleting node with both children, switch it with closest in order node
// swap values and delete the bottom node converting it to other cases
temp = node.GetSuccessor();
node.Interval = temp.Interval;
node.RecalculateMaxEnd();
while (node.Parent != Sentinel)
{
node = node.Parent;
node.RecalculateMaxEnd();
}
}
node = temp;
temp = node.Left != Sentinel ? node.Left : node.Right;
// we will replace node with temp and delete node
temp.Parent = node.Parent;
if (node.IsRoot)
{
Root = temp; // Set new root
}
else
{
// Reattach node to parent
if (node.ParentDirection == NodeDirection.RIGHT)
{
node.Parent.Left = temp;
}
else
{
node.Parent.Right = temp;
}
IntervalNode <TKey, TValue> maxAux = node.Parent;
maxAux.RecalculateMaxEnd();
while (maxAux.Parent != Sentinel)
{
maxAux = maxAux.Parent;
maxAux.RecalculateMaxEnd();
}
}
if (node.Color == NodeColor.BLACK)
{
RenewConstraintsAfterDelete(temp);
}
}
/// <summary>
/// General left rotation
/// </summary>
/// <param name="node">top of rotated subtree</param>
private void RotateLeft(IntervalNode <TKey, TValue> node)
{
var pivot = node.Right;
NodeDirection dir = node.ParentDirection;
var parent = node.Parent;
var tempTree = pivot.Left;
pivot.Left = node;
node.Parent = pivot;
node.Right = tempTree;
if (tempTree != Sentinel)
{
tempTree.Parent = node;
}
if (dir == NodeDirection.LEFT)
{
parent.Right = pivot;
}
else if (dir == NodeDirection.RIGHT)
{
parent.Left = pivot;
}
else
{
Root = pivot;
}
pivot.Parent = parent;
pivot.RecalculateMaxEnd();
node.RecalculateMaxEnd();
}