protected void _add(T value, bool balance)
{
AvlTreeNode <T> current = Head;
while (true)
{
if (value.CompareTo(current.Value) < 0)
{
if (current.Left == null)
{
current.Left = new AvlTreeNode <T>(value, current, this);
break;
}
current = current.Left;
}
else
{
if (current.Right == null)
{
current.Right = new AvlTreeNode <T>(value, current, this);
break;
}
current = current.Right;
}
}
if (balance)
{
while (current != null)
{
current.Balance();
current = current.Parent;
}
}
}
protected bool _remove(T value, bool balance)
{
AvlTreeNode <T> current = Find(value);
if (current == null)
{
return(false);
}
AvlTreeNode <T> treeToBalance = current.Parent;
Count--;
if (current.Right == null)
{
if (current.Parent == null)
{
Head = current.Left;
if (Head != null)
{
Head.Parent = null;
}
}
else
{
int compareResult = current.Parent.CompareNode(current);
if (compareResult > 0)
{
current.Parent.Left = current.Left;
}
else if (compareResult < 0)
{
current.Parent.Right = current.Left;
}
}
}
else if (current.Right.Left == null)
{
current.Right.Left = current.Left;
if (current.Parent == null)
{
Head = current.Right;
if (Head != null)
{
Head.Parent = null;
}
}
else
{
int compareResult = current.Parent.CompareNode(current);
if (compareResult > 0)
{
current.Parent.Left = current.Right;
}
else if (compareResult < 0)
{
current.Parent.Right = current.Right;
}
}
}
else
{
AvlTreeNode <T> leftmost = current.Right.Left;
while (leftmost.Left != null)
{
leftmost = leftmost.Left;
}
leftmost.Parent.Left = leftmost.Right;
leftmost.Left = current.Left;
leftmost.Right = current.Right;
if (current.Parent == null)
{
Head = leftmost;
if (Head != null)
{
Head.Parent = null;
}
}
else
{
int compareResult = current.Parent.CompareNode(current);
if (compareResult > 0)
{
current.Parent.Left = leftmost;
}
else if (compareResult < 0)
{
current.Parent.Right = leftmost;
}
}
}
if (balance)
{
if (treeToBalance != null)
{
treeToBalance.Balance();
}
else
{
if (Head != null)
{
Head.Balance();
}
}
}
return(true);
}
