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Heaps and Priority Queues Solution
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 max heap which means that each element in the heap will be greater than both of its children. The rst 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 Queue
You are to code a priority queue that is backed by your heap. See the interface for more information regarding implementation.
Grading
Here is the grading breakdown for the assignment. There are various deductions not listed that are incurred when breaking the rules listed in this PDF, and in other various circumstances.
Methods:
BuildHeap constructor
10pts
Heap add
17pts
Heap remove
18pts
Heap clear
5pts
PQ enqueue
10pts
PQ dequeue
10pts
PQ clear
5pts
Other:
Checkstyle
10pts
E ciency
15pts
Total:
100pts
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Homework 5: Heaps and Priority Queues Due: See T-Square
Keep in mind that some functions are dependent on others to work, such as remove methods requiring the add methods to work. Also, the size function is used many times throughout the tests, so if the size isn't updated correctly, many tests can fail.
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 o a point for every style error that occurs. If you feel like what you wrote is in accordance with good style but still sets o the style checker please email Raymond Ortiz (rortiz9@gatech.edu) with the subject header of \CheckStyle XML".
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 mes-sage 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:
Bad: throw new IndexOutOfBoundsException("Index is out of bounds.");
Good: 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<Integer() 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.
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Homework 5: Heaps and Priority Queues Due: See T-Square
break may only be used in switch-case statements
continue package
System.arraycopy() clone()
assert()
Arrays class Array class
Collections class
Collection.toArray()
Re ection APIs
Inner or nested classes Lambda Expressions Method References
If you're not sure on whether you can use something, and it's not mentioned here or anywhere else in the homework les, just ask.
Debug print statements are ne, but nothing should be printed when we run your code. We expect clean runs - printing to the console when we're grading will result in a penalty. If you submit these, we will take o points.
Provided
The following le(s) have been provided to you. There are several, but you will only edit two of them.
HeapInterface.java
This is the interface you will implement in MaxHeap. All instructions for what the methods should do are in the javadocs. Do not alter this le.
MaxHeap.java
This is the class in which you will implement HeapInterface. Feel free to add private helper meth-ods but do not add any new public methods, inner/nested classes, instance variables, or static variables.
PriorityQueueInterface.java
This is the interface you will implement in MaxPriorityQueue. All instructions for what the methods should do are in the javadocs. Do not alter this le.
MaxPriorityQueue.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.
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Homework 5: Heaps and Priority Queues Due: See T-Square
HeapPQStudentTests.java
This is the test class that contains a set of tests covering the basic operations on the MaxHeap and MaxPriorityQueue 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 le(s). Please make sure the lename matches the lename(s) below, and that only the following le(s) are present. T-Square does not delete les from old uploads; you must do this manually. Failure to do so may result in a penalty.
After submitting, be sure you receive the con rmation email from T-Square, and then download your uploaded les 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.
MaxHeap.java
MaxPriorityQueue.java
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