public bool Remove(TKey key)
{
var node = Find(key, _root);
if (node == null)
{
return(false);
}
Count--;
if (node == _root)
{
_root = Next(node);
}
if (node.Left == null && node.Right == null)
{
if (node.Parent.Left == node)
{
node.Parent.Left = null;
}
else
{
node.Parent.Right = null;
}
}
else
{
if (node.Left == null || node.Right == null)
{
if (node.Right != null)
{
node.Right.Parent = node.Parent;
if (node.Parent != null)
{
if (node.Parent.Left == node)
{
node.Parent.Left = node.Right;
}
else
{
node.Parent.Right = node.Right;
}
}
}
else
{
node.Left.Parent = node.Parent;
if (node.Parent != null)
{
if (node.Parent.Left == node)
{
node.Parent.Left = node.Left;
}
else
{
node.Parent.Right = node.Left;
}
}
}
}
else
{
var next = Next(node);
if (next.Parent == node)
{
next.Left = node.Left;
node.Left.Parent = next;
next.Parent = node.Parent;
if (node == node.Parent.Left)
{
node.Parent.Left = next;
}
else if (node == node.Parent.Right)
{
node.Parent.Right = next;
}
}
else
{
if (next.Right != null)
{
next.Right.Parent = next.Parent;
}
next.Parent.Left = next.Right;
next.Right = node.Right;
next.Left = node.Left;
node.Left.Parent = next;
node.Right.Parent = next;
next.Parent = node.Parent;
if (node.Parent != null)
{
if (node == node.Parent.Left)
{
node.Parent.Left = next;
}
else if (node == node.Parent.Right)
{
node.Parent.Right = next;
}
}
}
}
}
return(true);
}
public void Clear()
{
_root = null;
Count = 0;
}
/// <summary>
/// Creates a new, empty <see cref="T:Trees.BinaryTree"/> class. Like a sapling!
/// </summary>
public BinaryTree()
{
topNode = null;
}
/// <summary>
/// Creates a new <see cref="T:Trees.BinaryTree"/> class with the first nodze. Like a sapling!
/// </summary>
/// <param name="firstNodeVal">Top/first node value.</param>
public BinaryTree(T firstNodeVal)
{
topNode = new BinaryNode <T>(firstNodeVal);
}
/// <summary>
/// Makes a new node.
/// </summary>
/// <param name="val">The value of the new node.</param>
/// <param name="leftNode">The left of the new node.</param>
/// <param name="rightNode">The right of the new node.</param>
public BinaryNode(T val, BinaryNode <T> leftNode = null, BinaryNode <T> rightNode = null)
{
this.val = val;
left = leftNode;
right = rightNode;
}