CSCI 162 - Lecture 13 - Chapter 9: Trees (continued)

Instructor's Class Notes

     

  1. Binary Search Trees - In a binary search tree, the elements of the nodes can be compared with a total order semantics. These two rules are followed for every node n:
    1. Every element in n's left subtree is less than or equal to the element in node n.
    2. Every element in n's right subtree is greater than the element in node n.
    Example:


    Question 1: Where might we find the number 16?

    Question 2: How many comparisons to find the number 54?

    Question 3: What if these same numbers were stored in an unsorted bag? In a sorted bag?

    2.  

  2. BStree lab - For the BStree lab you must finish several methods of the BStree.java module. The BStree lab is here

    Files to include:
    1. BStree class - You need to finish four (4) methods in this class. BStree code is here
    2. TreeLines.java test program - This program asks the user for a line of input and then inserts the characters from that line into a tree and displays the resulting tree. The program then asks for another line and then removes those characters from the tree, again, printing the results. Use this program, as-is, for testing your BStree class.
    3. Btree class - This like BTnode below is part of the btree package that you must include in your project. Btree provides a class with helper methods for printing trees inorder, etc. Btree documentation and code.
    4. BTnode class - This is the generic binary tree node class used by your BStree class as well as the Btree helper class. See BTnode documentation and code.