public CircularItem <T> AddItemAfter(CircularItem <T> circItem, T value)
{
if (circItem == null)
{
return(AddItem(value));
}
CircularItem <T> item;
if (_removed != null)
{
item = _removed;
item.Value = value;
_removed = _removed.Next;
}
else
{
item = new CircularItem <T>(value);
}
item.Next = circItem.Next;
item.Previous = circItem;
circItem.Next.Previous = item;
circItem.Next = item;
Last = item;
return(Last);
}
public CircularItem <T> AddItem(T value)
{
CircularItem <T> item;
if (_removed != null)
{
item = _removed;
item.Value = value;
_removed = _removed.Next;
}
else
{
item = new CircularItem <T>(value);
}
if (Last != null)
{
item.Next = Last.Next;
item.Previous = Last;
Last.Next.Previous = item;
Last.Next = item;
}
else
{
item.Next = item;
item.Previous = item;
}
Last = item;
return(Last);
}
public void LinkTwoItem(CircularItem <T> left, CircularItem <T> right)
{
if (left.Next != right)
{
// есть кого удалять в кольце
right.Previous.Next = _removed;
_removed = left.Next;
_removed.Previous = null;
}
left.Next = right;
right.Previous = left;
Last = right;
}
public CircularItem <T> FindPrevious(CircularItem <T> from, Predicate <CircularItem <T> > match)
{
var result = from.Previous;
while (result != from)
{
if (match(result))
{
return(result);
}
result = result.Previous;
}
return(null);
}
public CircularItem <T> FindNext(CircularItem <T> from, Predicate <CircularItem <T> > match)
{
var result = from.Next;
while (result != from)
{
if (match(result))
{
return(result);
}
result = result.Next;
}
return(null);
}
public CircularList()
{
Last = null;
_removed = null;
}