CSC 216/s08/do right: Difference between revisions

Revision as of 02:32, 20 April 2008

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 coming soon.

The script

Video animation, teaches students how to insert and delete from a binary search tree. Also has a built in game that allows players to insert and remove nodes from a binary search tree.

@@ Line 8: / Line 8: @@
 Teaching the students how to '''insert''' and '''delete''' nodes from Binary Search Tree.
-<br>This includes:
+Insertion
-<br>How do we do insertion in a binary tree?
+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.
-<br>How do we delete a node from a binary search tree?
+Deletion
-    •If the node is a leaf node, then _______________?
-    •If the node has one child, modify ______________?
-    •If the node has two children, __________________?
 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.