Assignment 4 Black Jack Solution

$30.00 $26.40


You must do this assignment individually and, unless otherwise speci ed, you should follow all the instruc-tions. Graders have the discretion to deduct up to 15% of the value of this assignment for deviations from the general instructions and regulations.

Part 1, Question 1: 30 points

Part 1, Question 2: 10 points

Part 1, Question 3: 60 points

Part 2, Bonus: 10 points

110 points total

Free pass usage

If you wish to use your \free pass” (see the course webpage for more details), you are required to email the TA who is marking your assignment before the deadline. Please see the table below, which is referenced by the last name of the student, to determine your TA. Note that this is also the person whom you should see if you have questions or other complains about your marks.

TA Name

Email Address

Student Last Name Range

Teng Long


Andrew Holliday


Carlos Gonzalez Oliver


Hua Qun (Robin) Yan


Feras Abu Talib



David Bourque


Paul Husek


Babak Samari


Seyyed Mozafari


Egor Katkov


Chenghui Zhou


Jonathan Campbell


Neeth Kunnath


Ayush Jain


Tzu-Yang (Ben) Yu


Mohammad Patoary


Xiaozhong Chen


Stephanie La amme

YAY- Z (end)


Part 1

Note: Since this is a continuation of assignment 3, there is no warm up.

For this assignment, a 75% non-compilation penalty will apply. This means that if your code does not compile, you will receive a maximum of 25% for the question. If you are having trouble getting your code to compile, please contact your instructor or one of the TAs or consult each other on the discussion boards.

Question 1: Updating CardPile to use ArrayList (30 points)

For this question, you will add an additional method to the CardPile class. You will also modify the way we store the private property cards to take advantage of a new library object that we have used, speci cally ArrayList

The solutions for A3 will be released before A4 is due, so you can work with those. However, they can not be released until all students have handed in their A3’s (approximately November 25th).

In assignment 3, we implemented a CardPile class to represent a pile of cards. We did this using a private property of type Card[]. Now, we will modify our implementation to use ArrayList<Card> instead. This will improve the ease of use of some of the methods.

First, remove the private property Card[] cards and replace it with a private property ArrayList<Card> cards. Your code in the CardPile class will no longer compile. Update all of your methods so that they work with the new type.

You will notice that most methods are much simpler with ArrayList<Card> since the array list class takes care of some of the messier aspects of the array. You will also notice that once you nish making the update, if you’ve done everything properly, all your other classes from assignment three still work as expected. Make sure to re-test your card game class from assignment three to ensure you’ve made the updates correctly! This is one of the main advantages to declaring class attributes as private instead of public.

What you have done in this question is known as refactoring, which must be done quite frequently to any code base to keep it organized.

Hint: There is a library method in the Collections class that will let you shu e an ArrayList. You

can nd more information at

Question 2: Adding two new methods to CardPile (10 points)

In the previous assignment, we wrote a method makeFullDeck that produced a CardPile of 52 cards.

In this assignment, we will add two new methods:

makeFullDeck(int n) which is a static method and produces a pile of cards in which each of the 52 cards are represented n times. For example, if n is 3, then there should be 3 of each possible card, for a total of 156 Cards. This allows us to play card games that require more than one deck.

Note that you must keep your old makeFullDeck method in addition to the new method. Since this new method takes di erent input, we can overload the method name. Moreover, this new method is much easier to write if you make clever use of your old makeFullDeck method.

getNumCards() which takes nothing as input and returns the number of Cards in the CardPile.

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Question 3: BlackJack (60 points)

For this question you will implement a game of blackjack. An (abridged)1 version of the rules follows.

A player is playing the game against the casino (dealer). Each card is assigned point values (see below), and the goal is to have a hand of cards with as close to a score of 21 as possible without going over. A score of 21 is the best possible score. If it is obtained with only two cards, then it is called blackjack.

Both the player and the dealer are each initially given two cards. The player can see both their own cards, but only the second of the dealer’s cards.

After the cards are dealt, the player chooses whether to hit or stay. If they choose to hit, then they get an additional card. If they choose to stay, then the player’s turn is over and the dealer gets to play. The player will continue to choose until they either stay or go over 21. If the player goes over 21 (this is known as \busting”), then the player loses automatically no matter what the dealer does.

If the player stays at a score of 21 or lower, the dealer then plays. The dealer will always hit until their total is 18 or higher, at which point they will always stay.

If neither player busts, then the player whose score is closest to 21, but not over 21 wins. If both the player and the dealer have the same score, then they tie (also known as a \push”).

One last rule is that a player who is dealt \blackjack” (2 cards that total 21) automatically wins without the dealer getting to play at all unless the dealer is also dealt \blackjack” (2 cards that add up to 21) in which case it is a tie. This means that if the player gets \blackjack,” the dealer does not get a chance to play to try to get 21 as well.

Point values of each card: Two through Nine are worth 2-9 points each. 10, Jack, Queen, and King are each worth 10 points. Ace is worth either 1 or 11, whichever gives a better score. The suit is irrelevant.

For example, a hand of: 2 of Spades, 8 of Diamonds, King of Hearts is worth 20 points.

A hand of Ace of Spades, 8 of Diamonds, King of Hearts is worth 19 points.

A hand of Ace of Spades, King of Hearts is worth 21 points (and is blackjack).

A hand of Ace of Spades, Ace of Spades, Nine of Clubs is worth 21 points.

For further details and examples see: Remember that you are only required to implement this simpli ed version of the game for this assignment.

In order to do implement this, you will de ne a class Blackjack and are required to write the following helper methods in addition to your main method:

A static method getScore that takes as input a Card object and returns its score in blackjack. In this method, a card whose value is ACE should return 11.

A static method countValues that takes as input a CardPile object and returns its total blackjack score. This method should return the best possible score for a CardPile where \best” means as close to 21 as possible without going over.

A static method playRound that takes a CardPile as input and returns nothing. This method should execute one round of blackjack and in doing so will remove cards from the CardPile that was input. It must also use a Scanner to obtain user input, as the user needs to decide after each new card is dealt, whether to hit or stay. (Note: You can use .next() to read the next \word” typed by the user.) It is required that this method print all of the information that the user should have access to as well as the result of each round (including the full hand of the dealer).

In your main method, you must create a CardPile of 4 complete decks of cards and then play blackjack until there are fewer than or equal ( ) to 10 cards left in the deck.

  • Note that we have made several simpli cations to the rules to make it easier to implement. Speci cally, there are none of the more advanced rules such as \splitting” or \insurance”.

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Part 2: Bonus

Question 4: Gambling: Playing Blackjack for Money (10 points)

In order to obtain 10 bonus points2, modify the Blackjack class in the following ways to allow for betting money. Note that if you choose to do the bonus question, you should still submit only one version of the le since none of the changes should con ict. Make sure to double check, in this case, that the code for your bonus question does not adversely a ect the code for your previous questions.

De ne an enum corresponding to the di erent possible outcomes of a blackjack round: DEALER WINS, PLAYER WINS, TIE, BLACKJACK. This enum goes inside of the Blackjack class and is called Results.

Modify the playRound method to return the result of the round instead of void.

Modify the main method to obtain the initial pile of chips using args[0]. Assume it is an integer value.

Before each round, use a Scanner object to obtain the user’s bet for this round – make sure they only bet chips that they have. You may assume the user enters an integer.

After the round is over, update their chip pile according to the rules below.

The game now must also end if the player runs out of chips or chooses to leave. They can choose to leave by betting a negative amount.

Betting rules:

The user can bet only once before each round begins. If they lose, then they lose their bet. If they tie, their total chip count is unchanged. If they win, they win the amount that they bet. If they get blackjack then they win 1:5 times their bet (round down if the result is a fraction).

For example, if they have 50 chips, bet 10, and win, then they have 60 chips after the round. If they got blackjack, then they would have 65 chips at the end of the round. If they lost they would have 40 chips, and if they tied they would have 50 chips.

What To Submit

You have to submit one zip le with all your les in it to MyCourses under Assignment 4. If you do not know how to zip les, please ask any search engine or friends. Google might be your best friend with this, and a lot of di erent little problems as well.

These les should all be inside your zip.

Please name your zip le A4 where StudentId should be replaced by whatever your actual student id is.

confession.txt (optional) – You should write in this le any information that you think is useful for the TA to mark the assignment. This should include things you were not sure of as well as parts of your code that you don’t think it will work. Of course, like a confession, this will draw the TA’s attention to the part of your code that doesn’t work, but he/she will probably be more lenient than if he/she has to spend a lot of time looking for your error. It demonstrates that even though you couldn’t solve the problem, you understand roughly what is going on.

  • The bonus points will be added to your assignment four grade. If your assignment four grade is higher than 100 percent, then the bonus points will \carry over” to other assignments. If your assignments total more than 100 percent, then it can still help further improve your overall class grade when averaged with the test scores.

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