/**
* Insert an item into the tree
*
* @param {[type]} int Data the new item to add to the three
* @return true if the item was inserted (ie it was not already in the tree)
*/
public bool Insert(int Data)
{
TreeNode DataNode = new TreeNode(Data);
bool success = false;
treeLock.EnterWriteLock();
if(head == null){
head = DataNode;
success = true;
}else{
var node = head;
while(node != null && !success){
var LeftValid = node.Left != null;
var RightValid = node.Right != null;
if(DataNode.Data < node.Data){
if(LeftValid) node = node.Left;
else{
node.Left = DataNode;
success = true;
}
}else if(DataNode.Data > node.Data){
if(RightValid) node = node.Right;
else{
node.Right = DataNode;
success = true;
}
}else break;
}
}
treeLock.ExitWriteLock();
return success;
}
public SearchTree()
{
head = null;
treeLock = new ReaderWriterLockSlim();
}
//recursive helper routine for the InOrder enumerator
private IEnumerable<int> InOrder(TreeNode node)
{
if(node != null){
foreach(var x in InOrder(node.Left))
yield return x;
yield return head.Data;
foreach(var x in InOrder(node.Right))
yield return x;
}
}
public bool Remove(int value, TreeNode parent)
{
if(value < this.Data){
if(Left != null) return Left.Remove(value, this);
else return Right.Remove(value, this);
}else if(value > this.Data){
if(Right != null) return Right.Remove(value, this);
else return false;
}else{
if(Left != null && Right != null){
this.Data = Right.FindMin().Data;
Right.Remove(this.Data, this);
}else if(parent.Left == this){
parent.Left = (Left == null) ? Right : Left;
}else if(parent.Right == this){
parent.Right = (Left == null) ? Right : Left;
}
return true;
} // end mutex region
}
/**
* Remove an element from the tree.
*
* @param {[type]} int key @param key the data to be removed
* @return true if the item was removed without error
*/
public bool Remove(int key)
{
treeLock.EnterWriteLock();
if(head == null){
treeLock.ExitWriteLock();
return false;
}else {
if(head.Data == key){
var auxRoot = new TreeNode(0); //the 0 value is just a dumby value. Not used for anything
auxRoot.Left = head;
var result = head.Remove(key, auxRoot);
head = auxRoot.Left;
treeLock.ExitWriteLock();
return result;
}else{
var success = head.Remove(key, null);
treeLock.ExitWriteLock();
return success;
}
}
}
