Programming

Assignment 3 Specifications

Due: 19 February 2019 – class time.

Assignment: Write algorithms and programs to play ‘non-betting’ Craps. Craps is a game played with a pair of dice. In the game, the shooter (the player with the dice) rolls a pair of dice and the number of spots showing on the two upward faces are added up. If the opening roll (called the ‘coming-out’ roll) is a 7 (‘natural’) or 11 (‘yo-leven’), the shooter immediately wins the game. If the coming-out roll results in a 2 (‘snake eyes’), 3 (‘ace deuce’) or 12 (‘box cars’), then the shooter immediately loses the game (‘craps out’). Otherwise, the game continues and the total for the coming-out roll becomes the ‘point’. If the shooters rolls the point before rolling a 7, the shooter wins. If the shooter rolls a 7 before re-rolling the point, the shooter loses, otherwise the game continues. The shooter will continue to roll until they win or lose. Refer to https://en.wikipedia.org/wiki/Craps for the basics and typical names for the sum of the die rolls. Typical play-game pseudocode:

reset game;

roll two dice and sum;

increment number of rolls;

point = sum;

if (point is 7 or is 11)

game is won;

else if (point is (not 2), is (not 3) and is (not 12)) {

do {

roll two dice and sum;

increment number of rolls;

value = sum;

} while (value is (not point) and is (not 7));

if (value is point)

game is won;

else

game is lost;

else

game is lost;

}

Output: Output will provide the analysis of running a certain number of games of Craps – presented in clear, aligned, readable and attractive manner. The (win/lose) results of each game and the number of rolls will be recorded by the Analyzer class in order to facilitate an analysis of the game of Craps. Displayed analysis will include data points for:

(1) total number of games played,

(2) total number of rolls for all games played,

(3) average length (in rolls) of the games played (total rolls/total games),

(4) longest game played (in rolls).

(5) total number of games won,

(6) expected probability of winning overall,

(7) outcome of winning overall (total wins/total games),

(8) total number of wins that occurred on the coming-out roll,

(9) total number of games that ended on the opening (coming —out) roll,

(10) expected probability of winning on the opening roll,

(11) outcome of winning on the coming-out roll (coming-out wins/coming-out games),

(12) expected probability of the games ending on the coming-out roll,

(13) outcome of games ending on the coming-out roll (coming-out games/total games),

(14) total number of games continuing-on after the coming-out roll (wins & losses),

(15) expected probability of the games continuing-on after the coming-out roll,

(16) outcome of games continuing-on after the coming-out roll

((total games – coming-out games)/total games),

(17) summary tally of the number of rolls for each game to finish (1 to 21+),

* Coming-out games = total number of games that ended on the opening (coming-out) roll.

The display of the summary tally data point (17) can be printed horizontal or vertical (vertical is much easier), using all tallies, whose sum should be data point (2). Use of arrays is encouraged.

Empirical outcomes (data points 7, 11, 13, 16) are based upon actual results and will be computed and displayed as a decimal percentage to 4 decimal places. Average game length – data point (3) – will be displayed to 4 decimal places also. Expected probability values (data points 6, 10, 12, 15) should be displayed to 4 decimal places, proximate to the empirical outcomes for easy comparison. Sources for expected values should be documented – external sources for data point (6), or document your actual calculations for (data points 10, 12, 15). Data point labels (1-17) should be displayed next to appropriate results. See sample output below.

Input: Input will involve prompting the user for the number of games to be analyzed, an integer between 1 and 1,000,000, inclusive. Input validation is expected.

Requirements: Use only material covered in the first eight chapters. Style requirements as discussed in class expected. Efficiency should always be considered. Round only for output. Choose the most appropriate loop/decision structures and variable types. No switch or breaks statements allowed! No magic numbers! Use constants/enumerations where appropriate – game results, roll results, and so on. No graphics.

You must write at least three programs: one for the Die class, one for the Craps class (that uses the Die class) and one for the Analyzer (Driver/Main) class (that uses the Craps class). Review chapters three and eight for assistance with creating classes.

The Die class will provide instance variables and methods to support the rolling of a ‘fair’ die of any number of sides – an integer between 2-100, inclusive. Auto-correct invalid sides parameters: < 2 becomes 2, > 100 becomes 100, default = 6. The rollDie method will access the sides parameter and will return a random number between 1 and the number of sides, inclusive. Constructor(s) are required; other methods, as needed. Refer to the text – section 6.9, pages 283-284 – for a sample/similar Die class example. Use of java.util.Random is required.

The Craps class will provide constants (i.e. for sums of die rolls), instance variables and methods to play one game. A roll/throw in the game will consist of a pair of rollDie() method calls, or could be a single rollDice() method call. Since many games will be played (via the Analyzer), in addition to Constructor(s), the Craps class must also have a resetGame() method, a playGame() method, and ‘getter’ methods for the game results and the number of rolls needed to decide the game. Other methods, as needed.

The Analyzer class will prompt the user for the number games to be played, validate this input, and then conduct the requisite number of games, gathering the required statistics from each game for eventual analysis. See above (Output) for details. The main() should represent your high-level view of the required tasks – other methods, as needed. All input/output should be done from the Analyzer class. Remember, your programs are not allowed to crash – validate carefully, be mindful of array bounds, and watch for division by zero…

Submission: Your program must be able to compile and execute on FIU SCIS, using the ‘java’ compiler. Test it there before you submit.

Name your primary source code file: Analyzer.java; and your class source code files: Craps.java and Die.java . Submission must have three source code files.

Refer to the Canvas documents: “How to Develop a Simple Java Program” and “Style Guide” documents for details on required program and class format and documentation. Review all documents carefully! Note: the class source code files will use the class heading documentation, the analyzer (main) source code will use the program heading documentation.

Algorithm (pseudocode) should be submitted for each program, in a separate text file, and included with the Canvas posting and class submission.

Print out a copy of your primary source code, each class source code, the pseudocode and submit in class — signed, stapled and collated in the specified sequence: primary source code (w/main) file, two class source code files, and then the pseudocode text file(s).

Post a .zip file — with all source code (.java) and text files — on the Canvas web site. Do not include any extraneous (e.g. IDE, output) files in the Canvas submission.

Program documentation must include the required signed disclaimer (comment) in the heading — no grade will be assigned to programs that omit the disclaimer or signature.

Sample Output:

Summary of Game Statistics

+—————————————–+

| (1) Total Games 1000000 |

| (2) Total Rolls 3372851 |

| (3) Average Rolls 3.3729 |

| (4) Longest Game 44 |

+—————————————–+

Summary of Win Statistics

+———————————————————————————+

| Stat Games Outcome Expected |

+———————————————————————————+

| Total Wins 493449 (5) 0.4934 (7) 0.4929 (6) |

| Coming-Out Wins 222770 (8) 0.6666 (11) 0.6667 (10) |

| Coming-Out Games 334374 (9) 0.3344 (13) 0.3333 (12) |

+———————————————————————————+

Summary of Ending Statistics

+———————————————————————————+

| Stat Games Outcome Expected |

+———————————————————————————+

| Continuing-On Games 665626 (14) 0.6656 (16) 0.6667 (15) |

+———————————————————————————+

Summary of Game Lengths in Rolls (17)

+—————————————–+

| Rolls # of Games |

+—————————————–+

| 1 334374 |

| 2 187707 |

| 3 134314 |

| 4 96603 |

| 5 69067 |

| 6 49933 |

| 7 35915 |

| 8 25670 |

| 9 18458 |

| 10 13221 |

| 11 9617 |

| 12 6938 |

| 13 4998 |

| 14 3612 |

| 15 2649 |

| 16 1828 |

| 17 1440 |

| 18 984 |

| 19 722 |

| 20 516 |

| 21+ 1434 |

| – – – – – – – – – – – – – – – – – – – – |

| Total 1000000 |

+—————————————–+

Note: the values above are only representative, may not be accurate, and results will certainly vary.