BinaryNode <T> GetParentNode(BinaryNode <T> nodeToFind, BinaryNode <T> currentNode, BinaryNode <T> parentNode)
{
if (currentNode == null)
{
return(null);
}
else if (currentNode.Equals(nodeToFind))
{
return(parentNode);
}
var intComparison = nodeToFind.Value.CompareTo(currentNode.Value);
switch (intComparison)
{
case (0):
case (-1):
return(GetParentNode(nodeToFind, currentNode.Left, currentNode));
case (1):
return(GetParentNode(nodeToFind, currentNode.Right, currentNode));
default:
return(null);
}
}
void Remove(BinaryNode <T> currentNode, BinaryNode <T> parentNode)
{
if (currentNode == null)
{
return;
}
if (currentNode.Right != null)
{
var leftMostNode = FindLeftMostNode(currentNode.Right);
var leftMostNodeParent = GetParentNode(leftMostNode);
currentNode.Value = leftMostNode.Value;
if (leftMostNodeParent != null && leftMostNode.Right == null)
{
if (leftMostNodeParent.Equals(currentNode))
{
leftMostNodeParent.Right = null;
}
else
{
leftMostNodeParent.Left = null;
}
}
else
{
Remove(leftMostNode, leftMostNodeParent);
}
}
else if (currentNode.Left != null)
{
var leftChildValue = currentNode.Left.Value;
Remove(currentNode.Left, currentNode);
currentNode.Value = leftChildValue;
}
else
{
if (currentNode.Equals(Root))
{
Root = null;
return;
}
var compareInt = currentNode.Value.CompareTo(parentNode.Value);
switch (compareInt)
{
case (0):
case (-1):
parentNode.Left = null;
return;
case (1):
parentNode.Right = null;
return;
default:
return;
}
}
}
