CSC 216/s08/do right: Difference between revisions

Latest revision as of 19:03, 6 November 2008

Special Notes about Binary Search Trees

This is an example of a binary search tree

the left subtree of a node contains only values less than the node's value;
the right subtree of a node contains only values greater than or equal to the node's value.

Formatting Resources

Learning how Binary Search Tree Works

The problem

Teaching the students how to insert and delete nodes from Binary Search Tree.
Insertion
Insertion begins as a search would begin; if the root is not equal to the value, we search the left or right subtrees as before. Eventually, we will reach an external node and add the value as its right or left child, depending on the node's value. In other words, we examine the root and recursively insert the new node to the left subtree if the new value is less than the root, or the right subtree if the new value is greater than or equal to the root.
Deletion
There are several cases to be considered:

   * Deleting a leaf: Deleting a node with no children is easy, as we can simply remove it from the tree.
   * Deleting a node with one child: Delete it and replace it with its child.
   * Deleting a node with two children: Suppose the node to be deleted is called N. We replace the value of N with either its 
     in-order successor (the left-most child of the right subtree) or the in-order predecessor (the right-most child of the left 
     subtree).

Participants and props

Students can do this on their individual computers or on in groups. Only thing that is needed from the users computer is flash loaded on it.

Flash link Click Here

The script

Video animation, teaches students how to insert and delete from a binary search tree from the different cases mention above. This flash animation also has a built in game that allows players to insert and remove nodes from a binary search tree.

@@ Line 1: / Line 1: @@
+Special Notes about Binary Search Trees
+[[Image:Binary_search_tree.png|left|250px|thumb||This is an example of a binary search tree]]
+# the left subtree of a node contains only values less than the node's value;
+# the right subtree of a node contains only values greater than or equal to the node's value.
 ===Formatting Resources===
 [http://meta.wikimedia.org/wiki/Help:Wikitext_examples Formatting Help Guide from MetaWiki]
@@ Line 7: / Line 11: @@
 ===The problem===
-Teaching the students how to insert and delete nodes from Binary Search Tree.
+Teaching the students how to '''insert''' and '''delete''' nodes from Binary Search Tree.
-<br>This includes:
+<br>'''Insertion'''
-<br>How do we delete a node from a binary search tree?
+<br>Insertion begins as a search would begin; if the root is not equal to the value, we search the left or right subtrees as before. Eventually, we will reach an external node and add the value as its right or left child, depending on the node's value. In other words, we examine the root and recursively insert the new node to the left subtree if the new value is less than the root, or the right subtree if the new value is greater than or equal to the root.
-    •If the node is a leaf node, then ______________?
+<br>'''Deletion
-     •If the node has one child, modify ______________?
+'''
-     •If the node has two children, ______________?
+<br>There are several cases to be considered:
-<br>How do we do insertion in a binary tree?
+    * Deleting a leaf: Deleting a node with no children is easy, as we can simply remove it from the tree.
+     * Deleting a node with one child: Delete it and replace it with its child.
+     * Deleting a node with two children: Suppose the node to be deleted is called N. We replace the value of N with either its
+      in-order successor (the left-most child of the right subtree) or the in-order predecessor (the right-most child of the left
+      subtree).
 ===Participants and props===
 Students can do this on their individual computers or on in groups. Only thing that is needed from the users computer is flash loaded on it.
+[http://people.engr.ncsu.edu/efg/216/s08/video/t3/BinaryTree.swf Flash link Click Here]
 ===The script===
-Watch an interactive flash video insert and remove nodes from a binary search tree. Participate with the video by deciding how a binary search tree would look after adding or removing a node from the tree.
+Video animation, teaches students how to insert and delete from a binary search tree from the different cases mention above. This flash animation also has a built in game that allows players to insert and remove nodes from a binary search tree.