private static void RecursiveDeleteNodeChild(KwayTreeNode <T> node)
{
foreach (KwayTreeNode <T> next in node.Child)
{
RecursiveDeleteNodeChild(next);
next.Child = null;
}
}
public KwayTreeNode <T> GetNext(int id)
{
KwayTreeNode <T> node = SearchNode(id, out List <KwayTreeNode <T> > sibling);
int idx = sibling.IndexOf(node);
if (idx + 1 < sibling.Count)
{
return(sibling[idx + 1]);
}
else
{
return(null);
}
}
/// <summary>
/// Delete node from tree. If success, return true.
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
public bool DeleteNode(int id)
{
// Root NodeList, cannot delete
if (id == 0)
{
return(false);
}
KwayTreeNode <T> node = SearchNode(id, out List <KwayTreeNode <T> > sibling);
Debug.Assert(node != null);
Count -= CountLeaves(node);
RecursiveDeleteNodeChild(node);
sibling.Remove(node);
Count--;
return(true);
}
/// <summary>
/// Do not include root node itself.
/// </summary>
/// <param name="node"></param>
/// <returns></returns>
public int CountLeaves(KwayTreeNode <T> node)
{
Queue <List <KwayTreeNode <T> > > q = new Queue <List <KwayTreeNode <T> > >();
int leavesCount = 0;
q.Enqueue(node.Child);
while (0 < q.Count)
{
List <KwayTreeNode <T> > next = q.Dequeue();
foreach (KwayTreeNode <T> leaf in next)
{
leavesCount++;
if (0 < leaf.Child.Count)
{
q.Enqueue(leaf.Child);
}
}
}
return(leavesCount);
}
/// <summary>
/// Add node to tree. Returns node id. If fails, return -1.
/// </summary>
/// <param name="parentId"></param>
/// <param name="data"></param>
/// <returns></returns>
public int AddNode(int parentId, T data)
{
if (parentId == 0)
{ // Root NodeList
int id = _idList.Max() + 1;
_idList.Add(id);
KwayTreeNode <T> node = new KwayTreeNode <T>(parentId, id, data, null);
Root.Add(node);
Count++;
return(id);
}
else
{
int id = _idList.Max() + 1;
_idList.Add(id);
KwayTreeNode <T> parent = SearchNode(parentId);
Debug.Assert(parent != null);
KwayTreeNode <T> node = new KwayTreeNode <T>(parentId, id, data, parent.Child);
parent.Child.Add(node);
Count++;
return(id);
}
}
private static KwayTreeNode <T> RecursiveSearchNode(T data, List <KwayTreeNode <T> > list, out List <KwayTreeNode <T> > sibling)
{
foreach (KwayTreeNode <T> node in list)
{
if (data.Equals(node.Data))
{
sibling = list;
return(node);
}
if (0 < node.Child.Count)
{
KwayTreeNode <T> res = RecursiveSearchNode(data, node.Child, out sibling);
if (res != null)
{
return(res);
}
}
}
// Not found, return null
sibling = null;
return(null);
}
private KwayTreeNode <T> RecursiveSearchNode(int id, List <KwayTreeNode <T> > list, out List <KwayTreeNode <T> > sibling)
{
foreach (KwayTreeNode <T> node in list)
{
if (id == node.Id)
{
sibling = list;
return(node);
}
if (0 < node.Child.Count)
{
KwayTreeNode <T> res = RecursiveSearchNode(id, node.Child, out sibling);
if (res != null)
{
return(res);
}
}
}
// Not found, return null
sibling = null;
return(null);
}
