///// STUDENT TO FILL OUT ALL THE STUB METHODS IN THIS CLASS.

package tree234;

/**
* This is a modified version of an object-oriented implementation 2-3-4 trees given in class.
* It does not have the method isEmpty and uses appropriate helper methods to insert Integer
* objects in the tree.
* @since 12/08/00
* @author Dung X. Nguyen, Copyright 2000 - All Rights Reserved.
*/
public class Tree234
{
   /** @SBGen Variable (,,,64)   */
	private ANode234 _rootNode;

   /**
   * Initializes this Tree234 to empty.
   */
   public Tree234 ()
   {
//// STUDENT TO WRITE CODE.
   }

   /**
   * Inserts an Integer into this Tree234 without duplication.
   * @param n != null.
   * @throw IllegalArgumentException if n is null.
   */
   public final void insert (Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

  ///////////////////////////////////////
  //Not visible outside of package

   Tree234(ANode234 root)
   {
      _rootNode = root;
   }

   Tree234 (Tree234 lTree, Integer n, Tree234 rTree)
   {
      _rootNode = new Node2 (lTree, n, rTree);
   }

   final void changeRoot (ANode234 newRoot)
   {
	   _rootNode = newRoot;
   }

   final ANode234 root()
   {
	   return _rootNode;
   }

	/**
   * Helps the parent tree insert data, using the other two siblings if necessary.
   * @param parent the parent of this Tree234.
   * @param sib1 one of the two sibblings of this Tree234.
   * @param sib2 the sibling of sib1 and this tree.
   * @param n an Integer to be properly inserted into parent.
   */
   final void helpParentInsert (Tree234 parent, Tree234 sib1, Tree234 sib2, Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

	/**
   * Helps the parent tree insert data, using the one remaining sibling if necessary.
   * @param parent the parent of this tree.
   * @param sib one of the two sibblings of this Tree234.
   * @param n an Integer to be properly inserted into parent.
   */
   final void helpParentInsert (Tree234 parent, Tree234 sib, Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

	/**
   * Helps the parent tree insert data with the knowledge that all the sibling trees are empty.
   * Called by an empty sibling tree.
   * @param parent the parent of this Tree234.
   * @param n an Integer to be properly inserted into parent.
   */
   final void helpParentInsert (Tree234 parent, Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

   /**
   * Inserts data into this tree when its root node is a leaf.  Called by one of the empty subtrees.
   * @param n an Integer to be properly inserted into this Tree234.
   */
   final void insertAsLeaf (Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

   /**
   * Inserts data into this tree when its root node is NOT a leaf.  Called by a non-empty subtree.
   * @param n an Integer to be properly inserted into this Tree234.
   */
   final void insertNotAsLeaf (Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

   /**
   * This Tree234 is a subtree of a given parent tree.
   * Inserts n into this Tree234, splits, and re-attach to the parent tree if necessary
   * @param parent the parent of this Tree234.
   * @param n an Integer to be properly inserted into this Tree234.
   */
   final void insertAsChild (Tree234 parent, Integer n)
   {
//// STUDENT TO WRITE CODE.
   }

   /**
   * Attaches the 3 components of a 2-node to the root node in the proper order.
   * This Tree234 must be the parent of a non-empty Tree234.
   * @param lTree a 2-3-4 tree whose elements are less than n.
   * @param n a data element.
   * @param rTree a 2-3-4 tree whose elements are greater than n.
   */
   final void attach (Tree234 lTree, Integer n, Tree234 rTree)
   {
//// STUDENT TO WRITE CODE.
   }
}