/// <summary>
/// Output:
/// Last(source end
/// First(destnation end
/// </summary>
/// <param name="from"></param>
/// <param name="to"></param>
/// <returns></returns>
public static LinkedList <HierarchyTreeNode <T> > Path(HierarchyTreeNode <T> source, HierarchyTreeNode <T> destination)
{
///collect ancients ,find intersection
LinkedList <HierarchyTreeNode <T> > _sourceAncientList = new LinkedList <HierarchyTreeNode <T> >();
LinkedList <HierarchyTreeNode <T> > _destinationAncientList = new LinkedList <HierarchyTreeNode <T> >();
CollectAncients(source, _sourceAncientList);
CollectAncients(destination, _destinationAncientList);
//find out common ancient
LinkedListNode <HierarchyTreeNode <T> > _commonAncientNodeOnSource = _sourceAncientList.Last;
while (!_destinationAncientList.Contains(_commonAncientNodeOnSource.Value))
{
_sourceAncientList.RemoveLast(); //trim out source list as well
_commonAncientNodeOnSource = _sourceAncientList.Last;
}
//attach destionation list to source list (merge
LinkedListNode <HierarchyTreeNode <T> > _nextAttachingNode =
_destinationAncientList.Find(_commonAncientNodeOnSource.Value).Previous;
while (_nextAttachingNode != null)
{
_sourceAncientList.AddLast(_nextAttachingNode.Value); // value copy
_nextAttachingNode = _nextAttachingNode.Previous; //iterate
}
return(_sourceAncientList);
}
/// <summary>
/// Head(First : younger
/// End(Last : older
/// </summary>
/// <param name="start"></param>
/// <param name="list"></param>
static internal void CollectAncients(HierarchyTreeNode <T> start, LinkedList <HierarchyTreeNode <T> > list)
{
if (start != null)
{
list.AddLast(start);
CollectAncients(start.__parent, list);
}
else
{
//meet null
return;
}
}
/// <summary>
/// Member function version
/// First : source
/// Last : destination
/// </summary>
/// <param name="destination"></param>
/// <returns></returns>
public LinkedList <T> Path(HierarchyTreeNode <T> destination)
{
var __capsuleList = Path(this, destination);
var result = new LinkedList <T>();
var __node = __capsuleList.First;
while (__node != null)
{
result.AddLast(__node.Value.Value);
__node = __node.Next;
}
return(result);
}
void AddChild(T data)
{
var __node = new HierarchyTreeNode <T>(data);
__node.Parent = this;
}