public bool Delete(Node root, int value)
{
if (root == null) return false;
Node current = root;
Node Parent = null;
while (current != null) //Move to the node to be deleted
{
if (value > current.Data)
{
Parent = current;
current = current.Right;
}
else if (value < current.Data)
{
Parent = current;
current = current.Left;
}
else break;
}
if (current == null) return false;
//Check if the val to be deleted occurs more
//than once , then delete the bottom most occurence of it
if (current.Middle != null)
{ //and return
while (current.Middle != null)
{
Parent = current;
current = current.Middle;
}
Parent.Middle = null;
return true;
}
// If the node to be deleted has no child node.
if (current.Left == null && current.Right == null)
{
if (current == root)
{
root = null;
}
else if (Parent.Left == current)
Parent.Left = null;
else
Parent.Right = null;
return true;
}
//If the node to be deleted has only one child
if (current.Left == null)
{
if (current == root)
{
root = current.Right;
}
else if (Parent.Left == current)
Parent.Left = current.Right;
else Parent.Right = current.Right;
}
else if (current.Right == null)
{
if (current == root)
{
root = current.Left;
}
else if (Parent.Left == current) Parent.Left = current.Left;
else Parent.Right = current.Left;
}
else // If it has both left and right children.
{
Node ParentSuccessor = null;
Node CurrentSuccessor = FindSuccessor(current.Right, ref ParentSuccessor);
if (ParentSuccessor == null)
{
current.Data = CurrentSuccessor.Data;
current.Right = CurrentSuccessor.Right;
}
else
{
current.Data = CurrentSuccessor.Data;
ParentSuccessor.Left = CurrentSuccessor.Right;
}
}
Display(root);
return true;
}
public Trinary()
{
root = null;
}
public void Insert(int value)
{
Node newNode = new Node(value);
if (root == null)
{
root = newNode;
return;
}
Node current = root;
Node previous = null;
while (current != null)
{
previous = current;
if (value < current.Data)
{
current = current.Left;
}
else if (value > current.Data)
{
current = current.Right;
}
else
current = current.Middle;
}
if (value < previous.Data) previous.Left = newNode;
else if (value > previous.Data) previous.Right = newNode;
else previous.Middle = newNode;
}
Node FindSuccessor(Node Node, ref Node Parent)
{
if (Node == null)
{
Parent = null;
return null;
}
Parent = null;
while (Node.Left != null)
{
Parent = Node;
Node = Node.Left;
}
return Node;
}
public void Display(Node node)
{
if (node != null)
{
Display(node.Left);
}
if (node != null)
{
Debug.WriteLine(node.Data);
}
if (node != null && node.Middle != null)
{
Display(node.Middle);
}
if (node != null && node.Right != null)
{
Display(node.Right);
}
}
