(Latest Revision: 05/11/2000)
Working With Trees: Extending the Binary Search Tree Class
THE ASSIGNMENT:
Your assignment is to extend the Binary Search Tree ADT by adding the
following operations:
Name Type Purpose
PrintTree void function Print a representation of a
binary search tree to the standard
output.
SimilarTrees bool function Determine if two binary search
trees have the same shape.
LeafCount int function Determine the number of leaf
nodes in a binary search tree.
Ancestor void function Given the keyValue, print the
ancestors of a node in a binary
search tree.
In other words, you must make additions to BST2.h and BST2.cpp so
that bstClass makes the new operations available.
PrintTree:
The function PrintTree must have output like this:
Y This is a test string
W This is a test string
U This is a test string
T This is a test string
S This is a test string
Q This is a test string
O This is a test string
M This is a test string
L This is a test string
J This is a test string
I This is a test string
G This is a test string
F This is a test string
D This is a test string
B This is a test string
As you can see, the tree has been printed out "sideways" with
indentation used to to put each string into the correct position
relative to its "parent". Also, when the tree is rotated 90
degrees clockwise, the keys can be read in order from left to
right. Let's discuss how to do this in class. There is a very
simple way to implement this operation.
SPECIFICATIONS:
The first part of your assignment is to write the specifications
of each operation in the following format:
Operation (parameter list)
Function:
Inputs:
Preconditions:
Outputs:
Postconditions:
Here is an example that that shows how the format looks when
applied to a void function called FindNode. Your operations will
probably all have simpler postconditions than the ones for
FindNode.
void FindNode
( keyType keyValue ,
ptrType& nodePtr,
ptrType& parentPtr
);
Function:
- Find the node that contains keyValue;
Inputs:
- keyValue -- the key value of the tree node to be
sought.
Preconditions:
Outputs:
- nodePtr -- a pointer for the node sought, and parentPtr
- parentPtr -- a pointer for the parent of the node sought
Postconditions:
- If the search succeeds and the node sought is not the root node:
- then nodePtr points to the node sought, and
parentPtr points to the parent of the node
sought.
- If the search succeeds and the node sought is the root
node:
- then nodePtr points to the node sought, and
parentPtr is NULL.
- If the search does not succeed and the tree is not
empty:
- then nodePtr is NULL and parentPtr points to the
tree node that would be the parent of the node
sought, if that node were in the tree.
- If the tree is empty:
- then nodePtr is NULL and parentPtr is NULL.
Once you have specified the operations, you must implement
them. Use recursion wherever possible.
TESTING THE OPERATIONS:
Write a test plan describing the test cases needed for each
operation. Your grade is determined in part by the completeness
of your test plan.
Create a batch test driver program driver.cpp that executes
these test cases. The driver must write all output to standard
output (the screen).
It's important that the output of driver.cpp be
self-explanatory. Just from looking at the screen the user
must be able to tell what the inputs to each test are, what the
test does, and what the outcome is. For example use "before"
and "after" labels, statements, and calls to PrintTree to
accomplish this.
Your test driver is allowed to call any of the public operations
that are declared in the files BST2.h or Data.h. Of course,
your driver may also call any of the operations that you add by
making changes to bstClass.
WHAT TO TURN IN:
- On the first due date, turn in specifications for all
the new operations, a copy of your test plan, and the
code for at least 1 of the 4 new operations. Turn this
material in on paper. You must turn in your paper at
the start of class time on the due date.
- On the second due date, turn in your completed copies of
BST2.h, BST2.cpp, your driver.cpp file, and a script
showing the outcome of an execution. You must
shar all these materials into a single archive file
and send them via e-mail with subject line:
"CS2500P5Fin". Send the e-mail before
midnight, or the assignment will be considered late.
My e-mail address is:
john@ishi.csustan.edu
Please: It will really help me a lot in sorting
my mail if you use exactly the subject line given. (Note there
are no spaces.)
DUE DATES:
For due dates, see
the class schedule.