/// <summary>
/// Enumerates the nodes whose keys satisfy the given range predicate.
/// </summary>
/// <param name="rangePredicate">Must not conflict with the comparison delegate.</param>
public IEnumerable <TNode> FindRange(KeyRangePredicate rangePredicate)
{
TNode first = FindRangeMin(rangePredicate);
if (first == null)
{
yield break;
}
TNode last = FindRangeMax(rangePredicate);
last = last.successor;
for (TNode node = first; node != last; node = node.successor)
{
yield return(node);
}
}
private TNode FindRangeExtremum(KeyRangePredicate rangePredicate, RBTreeDirection direction)
{
TNode extremum = null;
TNode node = Root;
while (node != SentinelNode)
{
int result = rangePredicate(node.Key);
if (result == 0)
{
extremum = node;
node = node.GetChild(direction);
}
else if (result < 0)
{
node = node.right;
}
else
{
node = node.left;
}
}
return(extremum);
}
/// <summary>
/// Of the nodes whose keys satisfy the given range predicate,
/// returns the one with maximum key, if it exists.
/// Otherwise, returns null.
/// </summary>
/// <param name="rangePredicate">Must not conflict with the comparison delegate.</param>
public TNode FindRangeMax(KeyRangePredicate rangePredicate)
{
return(FindRangeExtremum(rangePredicate, RBTreeDirection.Right));
}