Comp 212 - Extra Credit Project
Rice University - Fall 2001
except code from your current Comp212 classmates. If your code is based on
materials that we did not provide you, just give us the appropriate references.
You are allowed and encouraged to work in teams of at most two
people. All team members will share the same grade.
The total grade of this project will added to the lowest exam grade of
each of the team member, not to exceed the maximum grade of the
You are not allowed to discuss the project in any way with anybody beside
your team member and the instructors (not the labbies) of this course.
Do not post your questions on the newsgroup. E-mail us, firstname.lastname@example.org
and email@example.com, your
questions instead. We will reply to you directly, and if deemed necessary,
forward our reply to the newsgroup as well. We will check our e-mail as often as
to catch your questions.
Write your code in the most object-oriented way possible, that is with the fewest number
of control statements and no checking of the states and class types of the objects
Create a subdirectory called xtra in your Comp212 directory for the
project. This subdirectory should contain:
- The project is open book/notes. It is absolutely optional and has no
negative effect on your final grade. You are allowed to consult any written
materials available under the sun,
The deadline for submission is Dec. 16, 2001 at 11:59 PM. No
late submission will be accepted. No extension will be granted.
Please e-mail us, firstname.lastname@example.org
and email@example.com, as soon as your
project is ready to be graded.
- An ASCII (or html) README
file to indicate what you have and/or have not done, and to point out
specific details that you feel we need to know when grading your work.
- UML diagrams with javadoc of all your class designs.
- All the Java source code necessary to compile and execute your test code.
- The original code for 2-3-4 trees (Tree234 ) discussed in the lecture includes the method
isEmpty() to check for the
state of the tree before making the insertion. Remove isEmpty() from
the 2-3-4 tree class and rewrite the insertion algorithm for 2-3-4 trees without checking for emptiness.
Feel free to
re-use the given existing code in any way you see fit. Feel free to add any
non-public method to the classes. Throw an IllegalStateException whenever is
appropriate. Write appropriate test code. 3 points
- Add a public method called boolean find(Integer n)
to look up a given Integer n and return true
if n is found in the 2-3-4 tree, false
otherwise. Write appropriate test code. 1 point.
- Add a public method called boolean remove(Integer n)
to remove a given Integer n. If n
is not in the 2-3-4 tree before the removal, then return false,
otherwise remove n from the 2-3-4 tree and return true.
Feel free to add non-public helper methods.
Write appropriate test code. 4 points
- Add the method toString() to the class Tree234 and appropriate methods to the node classes to compute
and return a String representation of Tree234 in the way similar to that of the toString() method for the binary tree class BiTree. Feel free to add non-public helper methods.
Below is an example of the required String representation. 2 points
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