Announcements, Homework, Lecture Outlines most recent first

Homework

• Complete Boggle by Wednesday 4:00 pm

Lecture

Lecture

Lecture

Lecture

Lecture

Lecture

Lecture

Wednesday 16-April

Announcements

• Important: The final three sections of 127B will be held in 930 Gould Simpson
  • 17- or 18-April  Work with partner on "An Event Driven Program": AnEventDrivenGUI.doc
  • 24- or 25-April  Work with partner on final project 
  • 1- or 2-May: Optional: Work with partner on final project
    • Test 2 is 2-May
• Repeat: Optional: Use OneMethodForSaveGameTest.java as a unit test with one method for testing GameTree save()  
  • You do NOT need to turn this in for full credit
• Repeat: Here is GameOf20GUI.java  (optionally use this to see if your game works, just don't turn it in).

Homework

• Begin OrderedMap
  • Note: the remove(E) algorithm will be discussed Friday, but you should be able to do all other methods

• Begin GUIs and Events

Monday 14-April

Announcements

• OneMethodForSaveGameTest.java  A unit test with one method for testing GameTree save()
• Repeat: Here is GameOf20GUI.java   (optionally use this to see if your game works, just don't turn it in)

Homework

• Finish Game of 20 Questions by Wednesday @ 10:00pm

• Binary Search Trees
  • implement find(E element)
  • maintain some BankAccounts
  • consider a remove algorithm
• A Map ADT

Friday 11-April

Announcements

• Here is the GameOf20GUI.java 

Homework

• Work on Project 9: Game of 20 Questions

• Demonstrate the Game of 20 Questions with Rick's GUI
• Binary Search Trees
  • implement insert and find

Wednesday 9-April

Announcements

• Reminder: Current  project (Game of 20 Questions ) is NOT due tonight
  • GUI now linked 

Homework

• Work on Project 9: Game of 20 Questions

• Continue with Expression Trees
  • add postFix to return a textual view of the tree in postFix 
  • add  inFix to return a textual view of the tree in inFix 
  • Write valueOf to evaluate the expression tree (only + and - operators)
  • add printSideways to show the structure of the tree (not ideal)
• Game of 20 Questions 
  • Demo with GameOf20GUI.java
    • Write the save method at the very end; after everything else is working

Monday 7-April

Announcements

• Reminder: Current  project (Game of 20 Questions ) is NOT due this week 

Homework

• Optionall
  • work on Project 9 
  • Watch Randy Pausch's Last Lecture http://www.youtube.com/watch?v=ji5_MqicxSo
    • ABC Special Wednesday night

• Continue with Expression Trees 
  • Write postFix to return a textual view of the tree in postFix 
  • Write inFix to return a textual view of the tree in inFix 
• Answer to 1C was wrong until 9:20 this morning
  • see Answers
• Take Quiz

Friday 4-April

Announcements

• Recursion Quiz 4 
  • Monday, 7-April
  • Practice Quiz handout from Wednesday: 127BPracticeQuiz4Spr08.pdf
    • Answers posted here by 5:00 pm Friday Night

Homework

• None (optionally begin Project 9) 

• Expression Trees 
  • Begin with the test to explain this new type: ExpressionTreeTest.java
  • Load ExpTreeStart.java, which won't compile
  • Write method build to construct the tree recursively (use a method like this on the next project)
  • Write inFix to return a textual view of the tree in infix notation (post fix if time permits)
• Play a game
• Introduce Project 9

Wednesday 2-April

Announcements

• Recursion Quiz 4 
  • Monday, 7-April
  • Practice Quiz handout  pdf

Homework

• Complete these 5 problems from the practice quiz with pencil and paper and hand in at the beginning of your section this week  1a, 2a, 3a, 4a, 5a 

• Begin Binary Trees

Monday 31-March

Announcements

• Short project 8 linked, due Thursday @ 8:00pm
• Recursion Quiz 4 will be Monday, 7-April
• Rich Saunders talk on the programming language Python
  • 6:30 pm, Tuesday 1-April 906 Gould Simpson
  • Free pizza in the 9th floor atrium
  • Sponsored by the Student Chapter of the ACM

Homework

• Read first 12 pages of Chapter 11: Binary Trees, pages 189 .. 200
  • Note: The tree traversals beginning on page 196 are another example of backtracking

• Turn in your hard copy solution of groupSum
• Discuss findTheExit algorithm (below) and Project 8
  • Reading from an input file (sample code from page 116).

Scanner keyboard = new Scanner(System.in);

String fileName = keyboard.nextLine();

Scanner inputFile = null;

try {

    // Throws exception if file with the input name can not be found

    inputFile = new Scanner(new File(filename));

}

catch (FileNotFoundException fnfe) {

  System.out.println("File not found: '" + fileName + "'");

}

// Treat scanner as a Scanner object with nextInt, hasNextLine, and nextLine

Friday 28-March

Announcements

• You are  invited to CS picnic Saturday 4:00 pm at Himmel Park  (SW corner)
  • RSVP to ACM President Drew Davidson andrewd@email.arizona.edu (who is buying the food) if plan to attend 

Homework

• Bring in a hard copy solution of groupSum found at http://javabat.com/prob?id=Recur2.groupSum
  • Due at the beginning of Monday's class  (3pts)
  • Hint: if stuck, read the hint.  
    • Rick adds use Java's or operator  ||

• Two problem solving strategies: 1) Divide and Conquer   2) Backtracking
• O(n log n)  Quicksort
  • There are two parts
    • the split algorithm to make some progress towards sorting, which is NOT recursive, and
    • the recursive method that specifies which portion to sort
• Backtracking 
  • N queens
  • Obstacle Course
  • JavaBat problem

Wednesday 26-March

Announcements

• 127B: You are  invited to CS picnic Saturday 4:00 pm at Himmel Park  (SW corner)
  • RSVP to ACM President Drew Davidson andrewd@email.arizona.edu

  

Homework

• Finish all 6 recursive methods
  • binarySeach must be O(log n), -10 if it is not

• More recursive examples  MoreRecursion.ppt
  • String commas(long): commas(12345678) would print 12,345,678
  • convert(int number, int base) Print a number in a different base
    • in class: make it work for  base 11..16
  • Find max in array using a private helper method
• Begin to explain Quicksort, which sort arrays O(n log n)
  • There are two parts
    • the split algorithm to make some progress towards sorting, which is NOT recursive, and
    • the recursive method that specifies which portion to sort

Monday 24-March

Announcements

• There will be no quiz today
  • Quiz 4 will be 7-April (only 5 quizzes, lowest still dropped)

Homework

• Read to end Chapter 10 Recursion, pages 174..188
  • Recursion with arrays and linked structures.

• Continue with Simple Recursion, begin at 10-16
  • Infinite recursion
  • Tail recursion
  • Recursion with arrays
    • Code demo: Sequential search
• Introduce project 6B: Three more recursive methods
• In-class

Wednesday 12-March

Announcements

• Go to 930 GS for section to complete the first 3 problems of next project and turnin via WebCat
• If necessary, go to lab during Friday's lecture 1:00-1:50pm

Homework

• By 1:50 pm Friday turn in RecursionFun 1, 2,  3 from WebCat (if Eclipse Submission is not working) :
  • From Eclipse right click on the Project name you wish to zip up into one file.
  • Then select Export > General > Archive File > Next
  • Browse to and name the archive file, PriorityList.zip for example.
  • Click Finish.
  • With your user name, password, and selecting the institution as University of Arizona, login to WebCat:   https://web-cat.cs.vt.edu/Web-CAT/WebObjects/Web-CAT.woa
  • Click the submit tab (upper left corner) and follow the submission instructions.

• Introduction to Simple Recursion 

Monday 10-March

Announcements

• This week will be different
  • Section leaders introduce recursion Wednesday
  • Go to 930 GS for section to complete the first 3 problems of next project and turnin via WebCat
  • If necessary, go to lab during Friday's lecture

Homework

• Read first 5 pages of Chapter 10 recursion, pages 169..173

• Test 1

Friday 7-March

Announcements

• Test 1 Monday, 10-March
  • All material, including USING ArrayList<E> , LinkedList<E> and using Iterator<E> (there will be NO implementation of Iterator<E>)

Homework

• Answers to the three quizzes handed out today.
• Practice quizzes are another resource of example test questions
  • Practice Quiz 1 with answers    MS-Word  or  PDF
  • Practice Quiz 2 with answers    MS-Word  or  PDF
  • Practice Quiz 3 with answers    MS-Word  or  PDF   (combined 4 questions with in class)

• Questions from anonymous survey
  • How does compareTo work?  What is Comparable?
    • Answer
      • compareTo is a commonly used way for Java to compare any two objects. 
      • compareTo is a binary operation that does NOT look like one
        • a.compareTo(b) < 0 is true when a < b
        • a.compareTo(b) >= 0 is true when  a > b
        • a.compareTo(b) == 0 is true when a equals b and b equals a
      • The Comparable interface is a way to guarantee that two objects can be compared to see if one is less than another
        • Used in Collections.binarySearch(List<E>, E)
        • Used in Collections.sort((List<E>)
        • In both, All elements in the list must implement the Comparable interface.
          • Code demo: What happens if you don't?  ComparableDemo.java and BankAccount.java  with and without implements Comparable<T>
            • In java 1.4, you woul get a ClassCastException, in Java 5, you get a compiletime error (better).
  • What is Iterator?
    • Answer See this as a Design Pattern Iterator.ppt
    • Code Demo: Total balance of all elements  in a list of BankAccounts UseIterator.java 
  • Difference between implements and extends?
    • extends means you get most methods and instance variables from the existing class that you extend.  You usually add instance variables, a constructor, and other methods
    • implements means the class must implement all methods of the interface 
  • When do you cast?
    • When a type is not the type expected by the compiler; mostly when using Object
      • example: compareTo argument must be a Comparable; need to cast Object to Comparable
      • an assignment expects a certain type: need to Cast Object to the expected type
      • If this is part of a method, you will not loose points on the test
  • More examples of Stacks
    • Answer: We have seen several applications of stacks, review them in the slides, book, or section handout. Stacks are last in, first out (LIFO)
      • Evaluating postfix expressions
      • Checking balanced symbols
      • Converting infix expressions to postfix
      • Expanding out into new MineSweeper squares until mines or squares are next to mines
  • More examples of Queues
    • We have only seen the operations, no applications.  Queues are FIFO, like a waiting line. Consider these applications
      • A queue maintains print job requests to process them in FIFO order
      • A queue on a router maintains packets to push them to their destination while receiving others, packets are processed FIFO
      • Same for test message packets or cell phone audio packets on the computers
      • A waiting line simulation to determine the average wait times of customers with 1, 2, or 3 cashiers. 
      • A Jukebox plays songs in FIFO order
        • Demonstrate this and show code

Monday 3-March

Announcements

• Test 1 Monday, 10-March
  • Iterators not on quiz, but will be on the test

Homework

• Finish MineSweeper  

• Make LinkedSet "iterable"
• Quiz 3, begin no later than 1:25

Wednesday 5-March

Announcements

• Repeat: Test 1 Monday, 10-March
  • All material, including today's List<E>, ArrayList<E>, and LinkedList<E>
• Test review session 
  • Thursday 7-March 5:30 pm to 7:00 pm 
  • 906 Gould Simpson
• Quiz Stats

Homework

• Study for Monday's test.  Use the 3 practice quizzes and the three quizzes
  • Practice Quiz 1 with answers    MS-Word  or  PDF
  • Practice Quiz 2 with answers    MS-Word  or  PDF
  • Practice Quiz 3 with answers    MS-Word  or  PDF   (combined 4 questions with in class)

• Introduce Java Collections Framework  2..13
• What is still unclear?
  • Anonymously, on a piece of paper, tell us what is still muddy or needs more examples
    • This should help us with the review session and Friday's test preview part of lecture.
    • Turn this in upside down on the table as you leave

Monday 3-March

Announcements

• Test 1 Monday, 10-March
  • Iterators not on quiz, but will be on the test

Homework

• Finish MineSweeper

• Make LinkedSet "iterable"
• Quiz 3, begin no later than 1:25

Friday 29-Feb

Announcements

• Repeating:
  • An archived (zip file) Eclipse project with MineSweeperGUI and a folder of pictures MineSweep.zip. After downloading this zip file,  
    • From Eclipse select   
      • File >  Import > Existing Projects into Workspace > Next
      • Check Select archive file
      • Click Browse
      • Use you explorer window or Finder to and open the zip file you just downloaded
      • Click Finish

Homework

• Work on MineSweeper
• Study for quiz
  • From Wednesday, practice quiz question FastQueue<E> with an answer pdf
  • Three more questions on Stacks and Queues  pdf

• Writing your own exceptions
  • Write a class that extends RuntimeException   (see EmptyQueueException.java on Code Demos Page)
• Add Iterator<E> iterator()  to ArraySet<E> (will not be linked since it is a project) 
• in class: Make LinkedSet "iterable"

Wednesday 27-Feb

Announcements

• NEW Added after class
  • Practice quiz question FastQueue<E> with an answer   pdf
  • An archived (zip file) Eclipse project with MineSweeperGUI and a folder of pictures MineSweep.zip. After downloading this zip file,  
    • From Eclipse select   
      • File >  Import > Existing Projects into Workspace > Next
      • Check Select archive file
      • Click Browse
      • Use you explorer window or Finder to and open the zip file you just downloaded
      • Click Finish

• MineSweeper now WebCatted
• You may import this Eclipse project, copy and paste your MineSweeper class and run the GUI.

Homework

• Work on MineSweeper

• Demo the MineSweeper project with the GUI
• Consider MinesweeperClearingTest.java Example unit test (also on code demos page)
  • Click row 2, column 1

       X X X X

       2 3 3 2 

       0 0 1 1

       0 0 1 X
  

• Writing your own exceptions
  • extend RuntimeException
• In-class: Develop FastQueue<E> implements  OurQueue<E> 
  • Use two external references: front and back
  • All methods must be O(1)

Monday 25-Feb

Announcements

• First part due tonight by 10:00pm: LinkedStack only (may have GamePiece or GameSquare)
• Second part will be Webcatted Tuesday 26-Feb
• Quiz 3 in one week
• Test 1 in two weeks

Homework

• Work on MineSweeper

• A few more things about MineSweeper  (see projects page)
  • Your class needs to add two constructors, see project from projects page
  • Should have a 2D array of GamePiece or Square objects to store information about one place that is clicked: has mine, how many mines around the square, is the square visible, flagged, checked? ... as suggested Friday
• Begin Queues  9-24.. 9-42

Friday 22-Feb

Announcements

• May have missed fail(); in section
  • To ensure a method throws an exception, add fail(); after the method that should have
  • Example code has been added to Part 1 of Minesweeper for fail has been added here
• Next project in 2 parts (that mean you will have 2 weeks)  
  • Both are now linked from the projects page
    • First part due Monday 25-Feb by 10:00pm: LinkedStack only (may have GamePiece)
    • First part due Monday 25-Feb by 10:00pm: MineSweeper implement MineSweeperModel

Homework

• Turn in LinkedStack by 10:00  p.m. Monday 25-Feb (published now on WebCat)
• Once you get 100%, Work on MineSweeper  (not published until Tuesday, 26-Feb)

• Introduce Project 5: MineSweeper, Part 1  (see projects page)
• Discuss algorithm for the click method and consider a new type to help
  • Suggestion: Do not have an 2D array of Char, have a 2D array of GamePiece objects
  • You should be able to push and pop GamePiece objects on your LinkedStack<E>
  • Take notes so you can develop your own GamePiece type

Wednesday 20-Feb

Announcements

• Next project in 2 parts (that mean you will have 2 weeks)  
  • First part due Monday 25-Feb by 10:00pm

Homework

• Read about Exceptions before Section
• Begin Part 1 of Project 5: LinkedStack<E> implements OurStack<E>

• Stacks
• Introduce Project 5: MineSweeper, Part 1  (see projects page)

Monday 18-Feb

Announcements

• None

Homework

• Read about Stacks in Chapter 9, pages 152,,159 

• Why linked lists?
  • Can conserve memory, as needed
  • When n is large, resizing array can be sloe and memory consuming
    • easier to insert
  • Some algorithms run faster
    • See runtimes on page 152
  • Easier to implement some collections (like stack and queue)
  • Good warmup for binary trees
• Practice Quiz answers, any questions?
• Quiz 2

Friday 15-Feb

Announcements

• Quiz 2 Monday, 18-Feb
• Quiz begins at 10:25 and ends at 10:50 

Homework

• Complete this practice quiz before Monday's class
  • MS-Word    or   pdf    

• Show another way to addFirst
• Implement the remove method in LinkedBag
  • Consider special cases of when first must change
• Consider adding in order (via pictures)
• Questions on Project 4? (projects page). Here's what's different 
  • You must use a singly linked structure
  • Big O requirements 
  • The class heading removes the need to cast to Comparable
• In class: begin the practice quiz.  Turn it in just before the quiz.

Wednesday 13-Feb

Announcements

• Quiz 2 Monday, 18-Feb
  • Practice Quiz will be posted Friday

Homework

• Read about linked structures in Chapter 8: List with a Linked Structure
  • pages 1..18 (hard copy)  or 127..144 (on line)

• Begin Linked Structures
• Introduce Project 4 (projects page). Here's what's different 
  • You must use a singly linked structure
  • Big O requirements 
  • The class heading removes the need to cast to Comparable

Monday 11-Feb

Announcements

• ACM Meeting Tuesday, 6:00pm. 9th floor atrium
• Quiz 2 : Monday 18-Feb

Homework

• Read about linked structures in Chapter 8: List with a Linked Structure
  • pages 1..18 (hard copy)  or 127..144 (on line)

• Reminder: Project 3 has four methods that need an upper bound (see grading criteria at the end of ArraySet<E>)
• In class Object, Autoboxing, add a method to a generic collection
• Begin Linked Structures

Friday 8-Feb

Announcements

• Project 3 has four methods that need an upper bound (see grading criteria at the end of ArraySet<E>)

Homework

• To help with the current project, Read all of chapter 7
  • A List interface
  • A class with an array instance variables to implement that interface
  • Array shifting during add and remove

• Continue with Collection Considerations, 22..34
• Demo sorting
  • Selection sort with people
  • Selection sort an array of BankAccounts without and with Comparable
  • Change Comparable
• In class Object, Autoboxing, add a method to a generic collection

Wednesday 6-Feb

Announcements

• Project 3 posted: ArraySet<E> implements OrderedSet<E>

Homework

• Begin project 3

• Continue with Collection Considerations, 6-5.. 6..20
• Introduce Project 3 (see Projects page)

Monday 4-Feb

Announcements

• Next project will be assigned Wednesday

Homework

• Read about ADTs, Data Structures and Java Collections in Chapter 6
  • All pages, 95..108

Quiz 1 is Monday, 4-Feb

• Up to 5 minutes to answer questions
• Quiz to begin at 1:05
• Quiz will take approximately 25 minutes
  • time announcements will be made at 10, 5, and 1 minutes
• About 20 minutes of lecture
  • Implement a simple generic collection with Object[]

Friday 1-Feb

Announcements

• Due dates for PiggyBank and GameOfLife are due tonight  by 10:00pm
• Quiz 1 is Monday, 4-Feb
  • up to 5 minutes to answer questions
  • Quiz to begin at 1:05
  • Quiz will take approximately 25 minutes
    • time announcements will be made at 10, 5, and 1 minutes
  • We will have about 20 minutes of lecture
  • Topics 
    • JUnit test with Assertions
    • A method that does 1-D array processing
    • A method in a class that does 2-D array processing
    • See practice quiz below 

Homework

• Take this Practice Quiz  MS-Word  or   PDF
  • Answers to Practice Quiz: MS-Word  or   PDF

• More Big Oh Slides 5-27..5-32
• Demo CompareSearches.java

Wednesday 30-Jan

Announcements

• WebCat login has been done since last night. You can Submit from Eclipse, but you can't login and change your password or use the file Upload option, therefore
  • GameOfLife project extended until Friday 1-Feb by 10:00 p.m. 

Homework

• Read to end of Chapter 5: Algorithm Analysis 
• If necessary, Work on Project 2: Game of life
  • You can submit if you are working in our lab or have installed the Submit plugin
  • http://sourceforge.net/project/showfiles.php?group_id=142064&package_id=160235

• Questions on Project 2: Game of Life?
• Algorithm Analysis 5-1..5-20

Monday 28-Jan

Announcements

• None 

Homework

• Work on Project 2: Game of life
• Read first 10 pages of Chapter 5: Algorithm Analysis 
  • On-line version: pages 79..87 
  • Bookstore version: Chapter 5 pages 1..9, stop at 5.4 Search Algorithms

• Answer this in-class together
• Add the WebCat Submit plugin to Eclipse (or at least try)
• Demo WebCat by submitting what Rick provided (probably a poor score) 
• Questions Project 2: Game of Life?
  • What is javadoc?  Why do we have comments with /** and @version and @author and @param
    • Because the PMS Style Checker complains
      • Submit the same file with no JavaDoc
    • More importantly, this helps when we use other people's "java-doxed" code
      • Show Java's API
      • What if you are using String substring, demo in Eclipse
  • Why do I not get 100% Code coverage?
    • You may not be calling toString. Feel free to Test toString with a test method like this:

    @Test

    public void testToString() {

      GameOfLife society = new GameOfLife(2, 10);

      String expected = "..........\n..........\n";

      assertEquals("O...O...O.\n..O...O...\n", society.toString());

• Will you give us a GUI?
  • Yes, here it is GameOfLifeGUI.java

Friday 25-Jan

Announcements

• Project 2 posted on projects page
• If you can not submit to WebCat, send Rick an email immediately or tell Rick at the end of class
• The PiggyBank section activity can still be turned into WebCat by Monday 12:45 (not a second later) 
• In C Sc 127B, you are expected to complete programming projects individually,
  • See syllabus section that begins with Academic Integrity and Penalties:

Homework

• Work on Project 2: Game of life

• Code demo: Matrix, a class with a 2D array (code to be linked on the code demos page)
  • constructor takes a 2D array of doubles
  • get(int, int) returns the value at a specified row and column
  • add(Matrix)  adds the Matrix argument to this Matrix
• Discuss Project 2: Game of Life
• in-class

Wednesday 23-Jan

Announcements

• See 18-Jan below if you have a hard copy of the book

Homework

• Turnin Project 1 by 10:00 p.m. tonight

Monday 18-Jan  3:00 pm

Announcements

• MLK Day, no classes
• If you are using the printed book (these changes have been made to the online version)
  • on page 14 of Chapter 4, change getTimesPlayedToday to songsPlayedToday in two places: 1) very first word on the page and 2) the method name 
  • on page 14, Change 

    for (int i = 0; i < datesPlayed.size(); i++) {

      if ((sameDay(today, datesPlayed.[i])

        result++;

    }

          to this

    for (int i = 0; i < n; i++) {          // 1) replace datesPlayed.size() with n

      if ((sameDay(today, datesPlayed[i])  // 2) remove the .

        result++;

    }

  • on page 15, Change   if (today.sameDay(mostRecentDatePlayed))
  •                        to this:    if (sameDay(today, mostRecentDatePlayed))

Friday 18-Jan

Announcements

• Project 1 posted. Due next Wednesday, 23-Jan at 110:00 p.m.  
  • Projects linked from the Project page
• Lab hours will be posted to the right by Tuesday, when they begin
  • Josh will be in the 228 Gould Simpson on Monday, 21-Jan (Martin Luther King Day) from 1:00 to 3:00 pm (one time only) to help with project 1,  Eclipse, and unit tests with JUnit
    • See lab hours link to the left for section leader lab hours on Tuesday 22-Jan and Wednesday 23-Jan

Homework

• Optional: Work through this short tutorial on using Eclipse for the first time
• Read pages 1..7 in Chapter 2: Objects, JUnit
• Optional: Skim the rest of chapter 2 and all of chapter 3, you should already know this
• Complete Project 1: Learn TDD in Chapter 4 by doing it 

• Demo Eclipse and unit testing with Eclipse
  • The code is posted on the code demos page

Monday 16-Jan

Announcements

• The textbook for this course is available  

  • As course notes in the UofA bookstore for less than $20.00 

  • or Free online

• Section will be held this week all in 942 Gould Simpson on Thursday and Friday
  

Homework

• Get your CS computer account ASAP
  • Go to 930 Gould Simpson, follow the yellow arrows and instructions to run the Apply program or from home at https://www.cs.arizona.edu/computing/services/account.html
  • Still need to go to 917 GS to get you account card
• Skim Chapter 1 (you should know all of this) and answer self-checks--Chapters linked from ricksBook

• Syllabus html or MS-Word