public bool Remove(T value)
{
p = -1;
ANode <T> node = _root;
while (node.IsNotNull())
{
path[++p] = node;
if (value.CompareTo(node.Item) == 0)
{
RemoveNode(node);
return(true);
}
if (value.CompareTo(node.Item) < 0)
{
node = node.Left;
}
else
{
node = node.Right;
}
}
return(false);
}
private void Print(ANode <T> root)
{
if (root.IsNotNull())
{
Print(root.Left);
Console.Write(root.Item + " ");
Print(root.Right);
}
}
public bool Add(T value)
{
if (IsEmpty)
{
// here just create the root node.
_root = new ANode <T>(value);
_root.BalanceFactor = 0;
return(true);
}
p = 0;
ANode <T> current = _root, prev = null;
while (current.IsNotNull())
{
path[p++] = current;
if (current.Item.CompareTo(value) == 0)
{
// item exists.
return(false);
}
prev = current;
current = (value.CompareTo(current.Item) < 0) ? current.Left : current.Right;
}
//
current = new ANode <T>(value);
current.BalanceFactor = 0;
if (value.CompareTo(prev.Item) < 0)
{
prev.Left = current;
}
else
{
prev.Right = current;
}
path[p] = current;
int bf = 0;
while (p > 0)
{
// compare to node's parent.
bf = (value.CompareTo(path[p - 1].Item) < 0) ? 1 : -1;
path[--p].BalanceFactor += bf; // change bf of parent node.
bf = path[p].BalanceFactor;
if (bf == 0)
{
// here means the tree is balanced.
return(true);
}
else if (Math.Abs(bf) == 2)
{
// Balance mimimum unbalanced tree.
RotateSubTree(bf);
return(true);
}
}
return(true);
}