public static IEnumerable <TKey> GetKeys <TKey>(this BstNodeBase <TKey> node, Func <TKey, bool> predicateForMin, Func <TKey, bool> predicateForMax)
{
for (var n = SearchMinNode(node, predicateForMin); n != null && predicateForMax(n.Key); n = SearchNextNode(n))
{
yield return(n.Key);
}
}
public static IEnumerable <TKey> GetKeys <TKey>(this BstNodeBase <TKey> node)
{
for (var n = SearchMinNode(node); n != null; n = SearchNextNode(n))
{
yield return(n.Key);
}
}
public static BstNodeBase <TKey> SearchPreviousNode <TKey>(this BstNodeBase <TKey> node)
{
if (node == null)
{
return(null);
}
return(SearchMaxNode(node.Left) ?? SearchPreviousAncestor(node));
}
public static BstNodeBase <TKey> SearchMaxNode <TKey>(this BstNodeBase <TKey> node)
{
if (node == null)
{
return(null);
}
return(SearchMaxNode(node.Right) ?? node);
}
public static BstNodeBase <TKey> SearchNextNode <TKey>(this BstNodeBase <TKey> node)
{
if (node == null)
{
return(null);
}
return(SearchMinNode(node.Right) ?? SearchNextAncestor(node));
}
public static void WalkByPreorder <TKey>(this BstNodeBase <TKey> node, Action <TKey> action)
{
if (node == null)
{
return;
}
action(node.Key);
WalkByPreorder(node.Left, action);
WalkByPreorder(node.Right, action);
}
public static BstNodeBase <TKey> RotateToLeft <TKey>(this BstNodeBase <TKey> node)
{
if (node == null)
{
throw new ArgumentNullException();
}
var p = node.Right;
node.Right = p.Left;
p.Left = node;
return(p);
}
public static BstNodeBase <TKey> SearchMaxNode <TKey>(this BstNodeBase <TKey> node, Func <TKey, bool> predicate)
{
if (node == null)
{
return(null);
}
if (predicate(node.Key))
{
return(SearchMaxNode(node.Right, predicate) ?? node);
}
else
{
return(SearchMaxNode(node.Left, predicate));
}
}
static BstNodeBase <TKey> SearchNextAncestor <TKey>(this BstNodeBase <TKey> node)
{
if (node?.Parent == null)
{
return(null);
}
if (node.Parent.Left == node)
{
return(node.Parent);
}
else
{
return(SearchNextAncestor(node.Parent));
}
}
static BstNodeBase <TKey> SearchPreviousAncestor <TKey>(this BstNodeBase <TKey> node)
{
if (node?.Parent == null)
{
return(null);
}
if (node.Parent.Right == node)
{
return(node.Parent);
}
else
{
return(SearchPreviousAncestor(node.Parent));
}
}
public static BstNodeBase <TKey> SearchNode <TKey>(this BstNodeBase <TKey> node, TKey key, Comparison <TKey> comparison)
{
if (node == null)
{
return(null);
}
var d = comparison(key, node.Key);
if (d == 0)
{
return(node);
}
if (d < 0)
{
return(SearchNode(node.Left, key, comparison));
}
else
{
return(SearchNode(node.Right, key, comparison));
}
}
