Description
Heaps
You are to code a heap that is backed by an array. This array will start at the capacity that is in
HeapInterface. Your heap will be a min heap which means that each element in the heap will be less
than both of its children. The first element in your heap should be at index 1. There should be nothing
in index 0. See the interface for more information regarding implementation.
Priority Queues
You are to code a priority queue that is backed by your heap. See the interface for more information
regarding implementation.
A note on JUnits
We have provided a very basic set of tests for your code, in HeapPQStudentTests.java. These tests
do not guarantee the correctness of your code (by any measure), nor does it guarantee you any grade.
You may additionally post your own set of tests for others to use on the Georgia Tech GitHub as a gist.
Do NOT post your tests on the public GitHub. There will be a link to the Georgia Tech GitHub as well
as a list of JUnits other students have posted on the class Piazza.
If you need help on running JUnits, there is a guide, available on T-Square under Resources, to help
you run JUnits on the command line or in IntelliJ.
Style and Formatting
It is important that your code is not only functional but is also written clearly and with good style. We
will be checking your code against a style checker that we are providing. It is located in T-Square, under
Resources, along with instructions on how to use it. We will take off a point for every style error that
occurs. If you feel like what you wrote is in accordance with good style but still sets off the style checker
please email Carey MacDonald (careyjmac@gatech.edu) with the subject header of “CheckStyle XML”.
1
Homework 5: Heaps and Priority Queues Due: See T-Square
Javadocs
Javadoc any helper methods you create in a style similar to the existing Javadocs. If a method is
overridden or implemented from a superclass or an interface, you may use @Override instead of writing
Javadocs. Any Javadocs you write must be useful and describe the contract, parameters, and return
value of the method; random or useless javadocs added only to appease Checkstyle will lose points.
Exceptions
When throwing exceptions, you must include a message by passing in a String as a parameter. The message must be useful and tell the user what went wrong. “Error”, “BAD THING HAPPENED”,
and “fail” are not good messages. The name of the exception itself is not a good message.
For example:
throw new PDFReadException(“Did not read PDF, will lose points.”);
throw new IllegalArgumentException(“Cannot insert null data into data structure.”);
Generics
If available, use the generic type of the class; do not use the raw type of the class. For example, use new
LinkedList() instead of new LinkedList(). Using the raw type of the class will result in a
penalty.
Forbidden Statements
You may not use these in your code at any time in CS 1332.
• break may only be used in switch-case statements
• continue
• package
• System.arraycopy()
• clone()
• assert()
• Arrays class
• Array class
• Collections class
• Collection.toArray()
• Reflection APIs
• Inner or nested classes
Debug print statements are fine, but nothing should be printed when we run them. We expect clean
runs – printing to the console when we’re grading will result in a penalty. If you use these, we will take
off points.
2
Homework 5: Heaps and Priority Queues Due: See T-Square
Provided
The following file(s) have been provided to you. There are several, but you will only edit two of them.
1. HeapInterface.java
This is the interface you will implement in MinHeap. All instructions for what the methods should
do are in the javadocs. Do not alter this file.
2. MinHeap.java
This is the class in which you will implement HeapInterface. Feel free to add private helper methods but do not add any new public methods, inner/nested classes, instance variables,
or static variables.
3. PriorityQueueInterface.java
This is the interface you will implement in MinPriorityQueue. All instructions for what the
methods should do are in the javadocs. Do not alter this file.
4. MinPriorityQueue.java
This is the class in which you will implement PriorityQueueInterface. Feel free to add private
helper methods but do not add any new public methods, inner/nested classes, instance
variables, or static variables.
5. HeapPQStudentTests.java
This is the test class that contains a set of tests covering the basic operations on the MinHeap and
MinPriorityQueue classes. It is not intended to be exhaustive and does not guarantee any type of
grade. Write your own tests to ensure you cover all edge cases.
Deliverables
You must submit all of the following file(s). Please make sure the filename matches the filename(s)
below, and that only the following file(s) are present. T-Square does not delete files from old uploads;
you must do this manually. Failure to do so may result in a penalty.
After submitting, be sure you receive the confirmation email from T-Square, and then download your
uploaded files to a new folder, copy over the interfaces, recompile, and run. It is your responsibility to
re-test your submission and discover editing oddities, upload issues, etc.
1. MinHeap.java
2. MinPriorityQueue.java
3
