public void AddingRecursively(Node <T> node, T data)
{
switch (ComparerT.Compare(node.Data, data) <= 0)
{
case true:
if (node.Right == null)
{
node.Right = new Node <T>(data);
Count++;
TreeEventArgs <T> args = new TreeEventArgs <T>(data, $"Element {data} was added into the tree");
ElementAdded?.Invoke(this, args);
}
else
{
AddingRecursively(node.Right, data);
}
break;
case false:
if (node.Left == null)
{
node.Left = new Node <T>(data);
Count++;
TreeEventArgs <T> args = new TreeEventArgs <T>(data, $"Element {data} was added into the tree");
ElementAdded?.Invoke(this, args);
}
else
{
AddingRecursively(node.Left, data);
}
break;
}
}
/// <summary>
/// Adds element to the tree according to comparer
/// </summary>
/// <param name="item">Object that should be added in tree</param>
/// <exception cref="ArgumentNullException">Thrown if parameter was null</exception>
public void Add(T item)
{
if (item is null)
{
throw new ArgumentNullException("item", "item can`t be null");
}
if (Root is null)
{
Root = new Node <T>(item);
Count++;
TreeEventArgs <T> args = new TreeEventArgs <T>(item, $"Element {item} was added into the tree(Root)");
ElementAdded?.Invoke(this, args);
}
else
{
AddingRecursively(Root, item);
}
}
/// <summary>
/// Adds element to the tree according to comparer
/// </summary>
/// <param name="item">Object that should be added in tree</param>
/// <exception cref="ArgumentNullException">Thrown if parameter was null</exception>
public void Add(T item)
{
if (item is null)
{
throw new ArgumentNullException("item");
}
var node = new BinaryTreeNode <T>(item);
var EventArg = new TreeEventArgs <T>(item, "Item has been added");
if (root == null)
{
root = node;
}
else
{
BinaryTreeNode <T> current = root, parent = null;
while (current != null)
{
parent = current;
if (Comparer.Compare(item, current.Value) < 0)
{
current = current.Left;
}
else
{
current = current.Right;
}
}
if (Comparer.Compare(item, parent.Value) < 0)
{
parent.Left = node;
}
else
{
parent.Right = node;
}
}
Count++;
ElementAdded?.Invoke(this, EventArg);
}
/// <summary>
/// Removes element from tree by its reference
/// </summary>
/// <param name="item">Object that should be removed from tree</param>
/// <returns>True if element was deleted succesfully, false if element wasn't found in tree</returns>
public bool Remove(T item)
{
Node <T> current = Root;
Node <T> father = null;
while (current != null)
{
if (ComparerT.Compare(current.Data, item) < 0)
{
father = current;
current = current.Right;
}
else if (ComparerT.Compare(current.Data, item) > 0)
{
father = current;
current = current.Left;
}
else
{
break;
}
}
if (current == null)
{
return(false);
}
Count--;
// checking if node is a leaf and deleting it
if (current.Right == null && current.Left == null)
{
// checking if node to delete is root
if (father == null)
{
Root = null;
}
// comparing what node of children should we use for replacing
else if (ComparerT.Compare(father.Data, current.Data) > 0)
{
father.Left = null;
}
else
{
father.Right = null;
}
}
//checking if node has only left child
else if (current.Right == null)
{
// checking if node to delete is root
if (father == null)
{
Root = current.Left;
}
else
{
father.Left = current.Left;
}
}
//checking if node has only right child
else if (current.Left == null)
{
// checking if node to delete is root
if (father == null)
{
Root = current.Right;
}
else
{
father.Left = current.Right;
}
}
// if node has both left and right
// we should replace node with the smallest node of right sub-tree
else
{
// temporary node to replace
Node <T> tmp = current.Right;
if (tmp.Left == null)
{
tmp.Left = current.Left;
}
else
{
while (tmp.Left.Left != null)
{
tmp = tmp.Left;
}
// one more temporary node, we need it for saving node to replace
Node <T> tmp2 = tmp.Left;
// deleting node from this place
tmp.Left = null;
tmp2.Left = current.Left;
tmp2.Right = current.Right;
tmp = tmp2;
}
if (father == null)
{
Root = tmp;
}
else if (ComparerT.Compare(father.Data, current.Data) > 0)
{
father.Left = tmp;
}
else
{
father.Right = tmp;
}
}
TreeEventArgs <T> args = new TreeEventArgs <T>(item, $"Element {item} was removed from tree");
ElementRemoved?.Invoke(this, args);
return(true);
}
/// <summary>
/// Removes element from tree by its reference
/// </summary>
/// <param name="item">Object that should be removed from tree</param>
/// <returns>True if element was deleted succesfully, false if element wasn't found in tree</returns>
public bool Remove(T item)
{
BinaryTreeNode <T> current;
// Find removal node
current = FindWithParent(item, out BinaryTreeNode <T> parent);
if (current == null)
{
return(false);
}
Count--;
if (current.Right == null)
{
if (parent == null)
{
root = current.Left;
}
else
{
int result = Comparer.Compare(parent.Value, current.Value);
if (result > 0)
{
parent.Left = current.Left;
}
else if (result < 0)
{
parent.Right = current.Left;
}
}
}
else if (current.Right.Left == null)
{
current.Right.Left = current.Left; if (parent == null)
{
root = current.Right;
}
else
{
int result = Comparer.Compare(parent.Value, current.Value);
if (result > 0)
{
parent.Left = current.Right;
}
else if (result < 0)
{
parent.Right = current.Right;
}
}
}
else
{
BinaryTreeNode <T> leftmost = current.Right.Left;
BinaryTreeNode <T> leftmostParent = current.Right;
while (leftmost.Left != null)
{
leftmostParent = leftmost;
leftmost = leftmost.Left;
}
leftmostParent.Left = leftmost.Right;
leftmost.Left = current.Left;
leftmost.Right = current.Right;
if (parent == null)
{
root = leftmost;
}
else
{
int result = Comparer.Compare(parent.Value, current.Value);
if (result > 0)
{
parent.Left = leftmost;
}
else if (result < 0)
{
parent.Right = leftmost;
}
}
}
var EventArg = new TreeEventArgs <T>(item, "Item has been removed");
ElementRemoved?.Invoke(this, EventArg);
return(true);
}