void DeleteFromParent(BSTNode node)
{
BSTNode parent = null;
FindParent(_root, node._key, ref parent);
if (parent != null)
{
if (node.Equals(parent._left))
{
parent._left = null;
}
else
{
parent._right = null;
}
}
}
// Удаление узла
void Delete(ref BSTNode deletingNode)
{
DeleteFromParent(deletingNode);
if (deletingNode._left == null)
{
if (deletingNode._right == null)
{
deletingNode = null;
}
else
{
Transplant(ref deletingNode, ref deletingNode._right);
}
}
else if (deletingNode._right == null)
{
Transplant(ref deletingNode, ref deletingNode._left);
}
else
{
var minNode = Minimum(deletingNode._right);
BSTNode minNodeParent = null;
FindParent(minNode, minNode._key, ref minNodeParent);
if (!minNodeParent.Equals(deletingNode))
{
Transplant(ref minNode, ref minNode._right);
minNode._right = deletingNode._right;
BSTNode minNodeRightParent = null;
FindParent(minNode._right, minNode._key, ref minNodeRightParent);
minNodeRightParent = minNode;
}
Transplant(ref minNode, ref minNodeParent);
minNode._left = deletingNode._left;
BSTNode minNodeLeftParent = null;
FindParent(minNode._right, minNode._key, ref minNodeLeftParent);
minNodeLeftParent = minNode;
}
}