private int FindClosestValueInBstHelperIterative(NodeBST root, int target, int closest)
{
NodeBST currentNode = root;
while (currentNode != null)
{
if (Math.Abs(target - closest) > Math.Abs(target - currentNode.Value))
{
closest = currentNode.Value;
}
if (target < currentNode.Value)
{
currentNode = currentNode.Left;
}
else if (target > currentNode.Value)
{
currentNode = currentNode.Right;
}
else
{
break;
}
}
return(closest);
}
private void InOrderRec(NodeBST root)
{
if (root != null)
{
InOrderRec(root.Left);
Console.WriteLine(root.Value);
InOrderRec(root.Right);
}
}
// search
public NodeBST Search(NodeBST rootNode, int item)
{
if (rootNode == null || rootNode.Value == item)
{
return(rootNode);
}
if (root.Value > item)
{
return(Search(root.Left, item));
}
return(Search(root.Right, item));
}
// recursive method to insert new items in the BST
private NodeBST InsertRec(NodeBST root, int item)
{
// if the tree is empty, return a new node
if (root == null)
{
root = new NodeBST(item);
return(root);
}
// otherwise, recur down the tree
if (item < root.Value)
{
root.Left = InsertRec(root.Left, item);
}
else if (item > root.Value)
{
root.Right = InsertRec(root.Right, item);
}
// return the unchanged node pointer
return(root);
}
private int FindClosestValueInBstHelper(NodeBST rootNode, int target, int closest)
{
if (rootNode == null)
{
return(closest);
}
if (Math.Abs(target - closest) > Math.Abs(target - rootNode.Value))
{
closest = rootNode.Value;
}
if (target < rootNode.Value)
{
return(FindClosestValueInBstHelper(rootNode.Left, target, closest));
}
else if (target > rootNode.Value)
{
return(FindClosestValueInBstHelper(rootNode.Right, target, closest));
}
else
{
return(closest);
}
}
// method that calls the recursive method InsertRec
public void Insert(int item)
{
root = InsertRec(root, item);
}
public BinarySearchTree()
{
root = null;
}