Project Detail

Description

Blackjack!


I. Introduction

This project will give you experience implementing abstract data
types, using interfaces (abstract base classes), and using
interface/implementation inheritance.

II. Blackjack (Simplified)

Blackjack, also sometimes called 21, is a relatively simple game
played with a standard deck of 52 playing cards. There are two
principals, a dealer and a player. The player starts with a bankroll,
and the game progresses in rounds called hands.

At the start of each hand, the player decides how much to wager on
this hand. It can be any amount between some minimum allowable wager
and the player's total bankroll, inclusive.

After the wager, the dealer deals a total of four cards: the first
face-up to the player, the second face-up to himself, the third
face-up to the player, the fourth face-down to himself.

The player then examines their cards, forming a total. Each card 2-10
is worth its spot value; each face card (jack, king, queen) is also
worth 10. An ace is worth either 1 or 11--whichever is more
advantageous to the player. If the total includes an ace counted as
11, the total is called "soft", otherwise it is called "hard".

Play progresses first with the player, then the dealer. The player's
goal is to build a hand that is as close to 21 as possible without
going over---the latter is called a "bust", and a player who busts
loses the hand without forcing the dealer to play. As long as the
player believes another card will help, the player "hits"---asks the
dealer for another card. Each of these additional cards is dealt
face-up. This process ends either when the player decides to
"stand"---ask for no cards---or the player busts. Note that a player
can stand with two cards; one need not hit at all in a hand.

If the player is dealt an ace plus any ten or face card, the player's
hand is called a "natural 21", and the player's wager is paid off with
3 to 2 odds, without examining the dealer's cards. In other words, if
the player had wagered 10, the player would win 15 if dealt a natural
21.

If the player neither busts nor is dealt a natural 21, play then
progresses to the dealer. The dealer *must* hit until he either
reaches a total greater than or equal to 17 (hard or soft), or busts.
If the dealer busts, the player wins. Otherwise, the two totals are
compared. If the dealer's total is higher, the player's bankroll
decreases by the amount of her wager. If the player's total is
higher, her bankroll increases by the amount of her wager. If the
totals are equal, the bankroll is unchanged; this is called a "push".
The only case where the hands are equal that is not a push is when the
player and dealer are each dealt natural 21s. In that case, the
player is still paid 3:2.

Note that this is a very simplified form of the game: we do not split
pairs, allow double-down bets, or take insurance. Likewise, a natural
21 for the dealer does not end the hand pre-emptively.

III. Programming Assignment

You will provide one or more implementations of four separate
abstractions for this project: a deck of cards, a blackjack hand,
a blackjack player, and a game driver. All files referenced in
this specification are located at:

/afs/engin.umich.edu/class/perm/eecs280/proj4

You may copy them to your private directory space, but may not modify
them in any way. This will help ensure that your submitted project
compiles correctly: for this project, the penalty for code that does
not compile will be severe, regardless of the reason.

III.a. The Deck ADT

Your first task is to implement the following ADT representing a deck
of cards:


class DeckEmpty { // An exception type
};

const int DeckSize = 52;

class Deck {
// A standard deck of 52 playing cards---no jokers
Card deck[DeckSize]; // The deck of cards
int next; // The next card to deal

public:

Deck();
// EFFECTS: constructs a "newly opened" deck of cards. first the
// spades from 2-A, then the hearts, then the clubs, then the
// diamonds. The first card dealt should be the 2 of Spades.

void reset();
// EFFECTS: resets the deck to the state of a "newly opened" deck
// of cards:

void shuffle(int n);
// REQUIRES: n is between 0 and 52, inclusive.

// MODIFIES: this

// EFFECTS: cut the deck into two segments: the first n cards,
// called the "left", and the rest called the "right". Note that
// either right or left might be empty. Then, rearrange the deck
// to be the first card of the right, then the first card of the
// left, the 2nd of right, the 2nd of left, and so on. Once one
// side is exhausted, fill in the remainder of the deck with the
// cards remaining in the othe rside. Finally, make the first
// card in this shuffled deck the next card to deal. For example,
// shuffle(26) on a newly-reset() deck results in: 2-clubs,
// 2-spades, 3-clubs, 3-spades ... A-diamonds, A-hearts.
//
// Note: if shuffle is called on a deck that has already had some
// cards dealt, those cards should first be restored to the deck
// in the order in which they were dealt, preserving the most
// recent post-shuffled/post-reset state.

Card deal();
// MODIFIES: this

// EFFECTS: returns the next card to be dealt. If no cards
// remain, throws an instance of DeckEmpty.

int cardsLeft();
// EFFECTS: returns the number of cards in the deck that have not
// been dealt since the last reset/shuffle.
};

The Deck ADT is specified in deck.h. The Deck ADT depends on the
following Card type:

enum Suit {
SPADES, HEARTS, CLUBS, DIAMONDS
};

extern const char *SuitNames[DIAMONDS+1];

enum Spot {
TWO, THREE, FOUR, FIVE, SIX, SEVEN, EIGHT, NINE, TEN,
JACK, QUEEN, KING, ACE
};

extern const char *SpotNames[ACE+1];

struct Card {
Spot spot;
Suit suit;
};

which is declared in card.h, implemented by card.cpp, and included by
deck.h. The file card.cpp defines SpotNames and SuitNames for you, so
that SuitNames[HEARTS] evaluates to "Hearts", and so on.

You are to put your implementation of this ADT in a file named
"deck.cpp". You *must* use *exactly* this name.

III.b. The Hand Interface

Your second task is to implement the following ADT representing a
blackjack hand:

struct HandValue {
int count; // Value of hand
bool soft; // true if hand value is a soft count
};

class Hand {
// OVERVIEW: A blackjack hand of zero or more cards
// Note: this really is the only private state you need!
HandValue curValue;
public:
Hand();
// EFFECTS: establishes an empty blackjack hand.

void discardAll();
// MODIFIES: this
// EFFECTS: discards any cards presently held, restoring the state
// of the hand to that of an empty blackjack hand.

void addCard(Card c);
// MODIFIES: this
// EFFECTS: adds the card "c" to those presently held.

HandValue handValue() const;
// EFFECTS: returns the present value of the blackjack hand. The
// count field is the highest blackjack total possible without
// going over 21. The soft field should be true if and only if at
// least one ACE is present, and its value is counted as 11 rather
// than 1. If the hand is over 21, any value over 21 may be returned.
//
// Note: the const qualifier at the end of handValue means that
// you are not allowed to change any member variables inside
// handValue. It is required because Players only get const Hands
// passed to them, and therefore can only call methods gauranteed
// not to change the hand.
};

The Hand ADT is specified in hand.h The Hand ADT depends on the Card
type, and includes card.h.

You are to put your implementation of this ADT in a file named
"hand.cpp". You *must* use *exactly* this name.

III.c. The Player Interface

Your third task is to implement three different blackjack players.
The interface for a Player is:


class Player {
// A virtual base class, providing the player interface
public:
virtual int bet(unsigned int bankroll,
unsigned int minimum) = 0;
// REQUIRES: bankroll >= minimum
// EFFECTS: returns the player's bet, between minimum and bankroll
// inclusive

virtual bool draw(Card dealer, // Dealer's "up card"
const Hand &player) = 0; // Player's current hand
// EFFECTS: returns true if the player wishes to be dealt another
// card, false otherwise.

virtual void expose(Card c) = 0;
// EFFECTS: allows the player to "see" the newly-exposed card c.
// For example, each card that is dealt "face up" is expose()d.
// Likewise, if the dealer must show his "hole card", it is also
// expose()d. Note: not all cards dealt are expose()d---if the
// player goes over 21 or is dealt a natural 21, the dealer need
// not expose his hole card.

virtual void shuffled() = 0;
// EFFECTS: tells the player that the deck has been re-shuffled.

virtual ~Player() { }
// Note: this is here only to suppress a compiler warning.
// Destructors are not needed for this project.
};


You are to implement three different classes derived from this
interface.

The first player is the Simple player, who plays a simplified version
of basic strategy for blackjack. The simple player always places the
minimum allowable wager, and decides to hit or stand based on the
following rules:

The first set of rules apply if the player has a "hard count"---his
best total counts an Ace (if any) for 1, not 11.

* If the player's hand totals 11 or less, he always hits.

* If the player's hand totals 12, he stands if the dealer shows 4,
5, or 6; otherwise he hits.

* If the player's hand totals between 13 and 16 inclusive, he
stands if the dealer shows a 2 through a 6 inclusive; otherwise
he hits.

* If the player's hand totals 17 or greater, he always stands.

The second set of rules apply if the player has a "soft count"---his
best total includes one Ace worth 11. (Note that a hand would never
count two Aces as 11 each--that's a bust of 22.)

* If the player's hand totals 17 or less, he always hits.

* If the player's hand totals 18, he stands if the dealer shows a
2, 7, or 8, otherwise he hits.

* If the player's hand totals 19 or greater, he always stands.

The Simple player does nothing for expose and shuffled events.

The second player is the Counting player. This player counts cards in
addition to playing the basic strategy. The intuition behind card
counting is that when the deck has more face cards (worth 10) than
low-numbered cards, the deck is favorable to the player. The converse
is also true.

The Counting player keeps a running "count" of the cards he's seen
from the deck. Each time he sees (via the expose() method) a 10,
Jack, Queen, King, or Ace, he subtracts one from the count. Each time
he sees a 2, 3, 4, 5, or 6, he adds one to the count. When he sees
that the deck is shuffled(), the count is reset to zero. Whenever the
count is +2 or greater, the Counting player bets double the minimum,
otherwise he bets the minimum. The Counting player should not
re-implement methods of the Simple player unnecessarily.

The final player you are to implement is the Competitor. The
Competitor can play any strategy you choose. The Competitor cannot
play the same strategy as the Simple or Counting players---there must
be some difference, however minor. The quality of the Competitor's
play will not count toward your grade. However, we will have a
tournament that evaluates each student's competitors under a large
number of hands. The top several Competitors will win fame, but
perhaps not fortune. To give you more incentive to come up with a
good Competitor, each member of the course staff will also enter a
Competitor. So, even if you don't beat the other students, you can
beat the Professors and GSIs!

All three of these Players must be implemented in a file named
"player.cpp". You must also declare a static global instance of each
of the three Players you implement in player.cpp. Finally, you should
implement the following "access" functions that return pointers to
each of these three players.

extern Player *get_Simple();

extern Player *get_Counting();

extern Player *get_Competitor();

Note: we've structured the Player as an Abstract Base Class so that
you have complete design freedom for the Competitor and its state.
Have fun!

III.d. The Driver program

Finally, you are to implement a Driver that can be used to simulate
this version of blackjack given your implementations of Deck and the
three Players. The driver program, when run, takes three arguments:

driver <bankroll> <hands> [simple|counting|competitor]

The first argument is an integer denoting the player's starting
bankroll. The second argument is the maximum number of hands to play
in the simulation. The final argument is one of the three strings
"simple", "counting", or "competitor", denoting which of the three
players to use in the simulation.

The driver first shuffles the deck. To shuffle the deck, you choose
seven cuts between 13 and 39 inclusive at random, shuffling the deck
with each of these cuts. We have supplied a header--rand.h--and
implementation--rand.cpp--that defines a function that provides these
random cuts. Each time the deck is shuffled, first announce it:

cout << "Shuffling the deckn";

And announce each of the seven cut points:

cout << "cut at " << cut << endl;

then be sure to tell the player via shuffle().

Then, while the player's bankroll is above the minimum bet of 5 and
there are hands left to be played:

* Announce the hand:

cout << "Hand " << thishand << " bankroll " << bankroll << endl;

* If there are fewer than 20 cards left, reshuffle the deck as
described above.

* Ask the player for a wager, and announce it:

cout << "Player bets " << wager << endl;

* Deal four cards: one face-up to the player, one face-up to the
dealer, one face-up to the player, and one face-down to the
dealer. Announce the face-up cards to cout: for example

Player dealt Ace of Spades
Dealer dealt Two of Hearts

Use the SpotNames and SuitNames arrays for this, and be sure to
expose() any face-up cards to the player.

* If the player is dealt a natural 21, immediately pay the player
3/2 of his bet. Note that, since we are working with integers,
you'll have to be a bit careful with the 3/2 payout. For
example, a wager of 5 would pay 7 if a natural 21 is dealt:
(3*5)/2 is 7 in integer arithmetic. In this case, announce the
win:

cout << "Player dealt natural 21n";

* If the player is not dealt a natural 21, have the player play his
hand. Draw cards until the player either stands or busts.
Announce and expose each card dealt as above.

* Announce the player's total

cout << "Player's total is " << p_count << endl;

and if the player busts, say so

cout << "Player bustsn";

deducting the wager from the bankroll and moving on to the next
hand.

* If the player hasn't busted, announce and expose the dealer's
hole card. For example:

Dealer's hole card is Ace of Spades

(Note: the hole card is NOT exposed if either the player busts
or is dealt a natural 21.)

* If the player hasn't busted, play the dealer's hand. The dealer
must hit until reaching seventeen or busting. Announce and
expose each card as above.

* Announce the dealer's total

cout << "Dealer's total is " << p_count << endl;

and if the dealer busts, say so

cout << "Dealer bustsn";

crediting the wager from the bankroll and moving on to the next
hand.

* If neither the dealer nor the player bust, compare the totals and
announce the outcome. Credit the bankroll, debit it, or leave it
unchanged as appropriate.

cout << "Dealer winsn";
cout << "Player winsn";
cout << "Pushn";

Finally, when the player either has too little money to make a minimum
wager *or* the allotted hands have been played, announce the outcome:

cout << "Player has " << bankroll << " after "
<< thishand-1 << " handsn";

III.d Implementation Rules

* You may #include <iostream>, <iomanip>, <string>, <cstdlib>, and
<cassert>. No other system header files may be included, and you
may not make any call to any function in any other library (even
if your IDE allows you to call the function without including the
appropriate header file). You may also include <cmath>, but only
for use in your Competitor. Other include files for your
Competitor may be allowed at the discretion of the course staff,
so just ask.

* Input and/or output should only be done where it is specified.

* No gotos.

* No global variables in the driver. You may use global state in
the class implementations, but it must be static and (except for
the three players) const.

* There is no user input. You may assume that functions are called
consistent with their advertised specifications. This means you
need not perform error checking. However, when testing your code
in concert, you may use the assert() macro to program
defensively.

* You are strongly discouraged from using any dynamic memory
facilties (new/delete and friends), but are allowed to do so in
your Competitor if you so choose.

IV. Testing

For this project, you are required to write, describe, and submit
individual, focused test cases for a Deck and a Counting Player. For
both of these ADTs, determine the behaviors required of the
implementation. Then, for each of these behaviors:

* list the *specific* behavior that the implementation must exhibit
in at most three sentences, and

* write a program that, when linked against the implementation
tests for the presence/absence of that behavior.

For the deck and the counting player, submit the following files

<impl>.overview -- the list of behaviors and test case filenames.

<impl>.case.1.cpp -- the first test case named in <impl>.overview
<impl>.case.2.cpp -- the second
...
<impl>.case.n.cpp -- the Nth.

For example, if you identify three behaviors in Deck, and two in the
Counting player, there would be seven files:

deck.overview
deck.case.1.cpp
deck.case.2.cpp
deck.case.3.cpp
player.overview
player.case.1.cpp
player.case.2.cpp

Be *sure* to use the correct filenames, or you will not receive full
credit!

Test cases in this project are "acceptance tests". Your deck tests
(each of which includes at least a main() function) will be linked
against a correct card.cpp and a possibly incorrect deck.cpp. Your
player tests (each of which includes at least a main() function) will
be linked against a correct card.cpp, a correct hand.cpp, and a
possibly incorrect player.cpp.

Your test case must decide, based on the results from calls to
deck/player methods, whether the deck/counting player is correct or
incorrect. If your case believes the deck/player to be correct, it
should return 0 from main(). If your case believes the deck/player to
be incorrect, it should return any value other than zero---the value
-1 is commonly used to denote failure. We do not compare the output
of your test cases against correct/incorrect implementations, but you
may find that such output is useful for your own testing, and you are
free to make use of as much as you like.

Here is an example of code that tests a hypthetical "integer add"
function (declared in addInts.h) with an "expected" test case:

// Tests the addInts function
#include "addInts.h"
int main()
{
int x = 3;
int y = 4;
int answer = 7;

int candidate = addInts(x, y);
if (candidate == answer) {
return 0;
} else {
return -1;
}
}

We will write a collection of decks/players with different, specific
bugs. You will be evaluated based on how many of our buggy versions
your test cases identify. If your test case mis-identifies a correct
library as buggy, it will not be used to evaluate buggy libraries.
So, for example, writing a test case that returns non-zero in all
cases will generate no credit.


V. Building the project

This project has several components: when complete, there are six
source files. To build the program, type the following all on one
line (making sure you've copied all header files):

g++ -Wall -Werror -o blackjack driver.cpp deck.cpp hand.cpp
player.cpp rand.cpp card.cpp

If you want to see only if a single file compiles cleanly, you can
compile it individually using the "-c" flag. For example, to check
your deck:

g++ -Wall -Werror -c deck.cpp

Programs that do not compile cleanly will be severely penalized in
this project, so be sure to check them in the CAEN environment.

We have supplied one simple set of output produced by a correct deck,
hand, simple player, and driver. It is called sample.txt. To test
your ensemble, do the following:

$ ./blackjack 100 3 simple > test.out
$ diff test.out sample.txt
$

If diff reports any differences at all, you have a bug.

VI. Handing in and grading

Use the submit280 program to submit the following files in project 4:

deck.cpp -- your Deck implementation
player.cpp -- your three Players
driver.cpp -- your simulation driver
hand.cpp -- your Hand implementation
deck.overview -- overview of your deck test cases
deck.case.1.cpp -- first deck test case
...
deck.case.N.cpp -- Nth deck test case
player.overview -- overview of your Counting Player test cases
player.case.1.cpp -- first player test case
...
player.case.N.cpp -- Nth player test case

IMPORTANT NOTE: You must submit ALL of your files with a SIGNLE
invocation of submit280. DO NOT SUBMIT YOUR FILES INDIVIDUALLY.

There are three components to your grade in this project: correctness
of deck, player, driver, and hand; testing of deck and player; and the
style of your deck, player, driver, and hand implementations.