/// <summary>
/// Default constructor
/// </summary>
public BinarySearchTree()
{
_root = null;
Count = 0;
_comparer = Comparer <T> .Default;
}
/// <summary>
/// Removes element from the binary search tree
/// </summary>
/// <param name="value">Value to remove</param>
/// <returns>True, if tree doesn't contain same value, false otherwise</returns>
public bool Remove(T value)
{
if (!Contains(value))
{
return(false);
}
BinarySearchTreeNode <T> parent = null;
BinarySearchTreeNode <T> current = FindWithParent(value, out parent);
BinarySearchTreeNode <T> replacementNode = null;
BinarySearchTreeNode <T> replacementNodeParent = null;
if (current.Right == null)
{
replacementNode = current.Left;
}
else if (current.Left == null)
{
replacementNode = current.Right;
}
else
{
replacementNodeParent = current;
replacementNode = current.Left;
while (replacementNode.Right != null)
{
replacementNodeParent = replacementNode;
replacementNode = replacementNode.Right;
}
if (replacementNodeParent == current)
{
replacementNode.Right = current.Right;
}
else
{
replacementNode.Right = current.Right;
replacementNodeParent.Right = replacementNode.Left;
replacementNode.Left = replacementNodeParent;
}
}
if (current == _root)
{
_root = replacementNode;
}
else if (_comparer.Compare(current.Value, parent.Value) < 0)
{
parent.Left = replacementNode;
}
else
{
parent.Right = replacementNode;
}
Count--;
return(true);
}
