Project 09 Description

For this lab you will write a Java program that plays the game Poker Dice. In this game, five dice are rolled and scored as if they were a hand of playing cards. The game goes through two separate phases. In the first phase, a "hand" of dice is presented to the player. The player then selects which dice he wants to keep and which he wants to re-roll. Once that decision is finished, all of the dice that the player has marked to re-roll are re-rolled and the final "hand" of dice is displayed. The hand should then be scored according to the rules of Poker Dice (given below) and the result displayed on the screen.

Scoring Poker Dice

The following table shows the values of different Poker Dice hands in order (i.e. Five of a Kind beats Four of a Kind, Four of a Kind beats Full House, etc.):

Hand	Description	Examples
Five of a Kind	All five dice show the same value	[1, 1, 1, 1, 1] [5, 5, 5, 5, 5]
Four of a Kind	Four of the five dice show the same value	[1, 2, 1, 1, 1] [4, 4, 4, 3, 4]
Full House	Three of the five dice show the same value, the other two show a different matched value	[1, 2, 2, 1, 1] [3, 3, 3, 5, 5]
Three of a Kind	Three of the five dice show the same value, the other two show different values	[1, 2, 3, 1, 1] [3, 3, 3, 2, 5]
Straight	All five dice together show a sequence of values 1-5 or 2-6 or 3-7 etc.	[2, 3, 1, 5, 4] [6, 3, 2, 4, 5]
Two Pair	Two of the five dice show the same value, and two other dice show a different shared value	[1, 2, 2, 1, 3] [3, 5, 6, 3, 6]
One Pair	Two of the five dice show the same value, the other dice show different values	[1, 2, 2, 3, 4] [3, 5, 6, 3, 1]
Highest Card X	If none of the above hands exist, then the score for the hand is "Highest Card X" where X is the highest value in the list	[1, 2, 3, 5, 7] - Highest Card 7 [1, 2, 8, 4, 5] - Highest Card 8

Note that for scoring, only the highest score is reported. So a hand like [5, 5, 5, 5, 5] should only be reported as "Five of a Kind" even though it also fits the definition of "Four of a Kind" and "Two Pair" etc. The idea behind scoring is that the hand is scored with only the best possible result, and scores are showed in descending order in the table above. In this assignment you are required to implement a scoring function that scores all of the above hands EXCEPT for the Straight. Your code must correctly score 5 of a kind, 4 of a kind, full house, three of kind, two pair, one pair, and highest card X "hands" of dice. For up to 2 points of extra credit, you may add the ability to score Straights to your scoring function. Indicate in the comments of your code that your code scores Straights as well as the other hands. For this assignment you must start with the following "skeleton" of Java code (listed below). Import this into your Eclipse workspace and fill in the methods as directed. For this assignment you WILL want to add extra methods beyond the methods defined in the skeleton. Feel free to add any methods you find useful, but make sure that you add comments indicating what they do following the form of the rest of the comments in the code.

public class Project10 { public static void main(String[] args) { // Fill in the body } // Given an array of integers as input, sets every element of the array to zero. public static void resetDice(int[] dice) { // Fill in the body } // Given an array of integers as input, checks each element of the array. If the value // of that element is zero, generate a number between 1 and 10 and replace the zero with // it. Otherwise, leave it as is and move to the next element. public static void rollDice(int[] dice) { // Fill in the body } // Given an array of integers as input, create a formatted String that contains the // values in the array in the order they appear in the array. For example, if the // array contains the values [0, 3, 7, 5, 2] then the String returned by this method // should be "0 3 7 5 2". public static String diceToString(int[] dice) { // Fill in the body } // Given an array of integers and a Scanner as input, prompt the user with a message // to indicate which dice should be re-rolled. If the user enters a valid index (between // 0 and the total number of dice -1) then set the die at that index to zero. If the // user enters a -1, end the loop and return to the calling program. If the user enters // any other invalid index, provide an error message and ask again for a valid index. public static void promptForReroll(int[] dice, Scanner inScanner) { // Fill in the body } // Given a Scanner as input, prompt the user to play again. The only valid entries // from the user are 'Y' or 'N', in either upper or lower case. If the user enters // a 'Y' the method should return a value of true to the calling program. If the user // enters a 'N' the method should return a value of false. If the user enters anything // other than Y or N (including an empty line), an error message should be displayed // and the user should be prompted again until a valid response is received. public static boolean promptForPlayAgain(Scanner inScanner) { // Fill in body } // Given an array of integers, determines the result as a hand of Poker Dice. The // result is determined as: // * Five of a kind - all five integers in the array have the same value // * Four of a kind - four of the five integers in the array have the same value // * Full House - three integers in the array have the same value, and the remaining two // integers have the same value as well (Three of a kind and a pair) // * Three of a kind - three integers in the array have the same value // * Two pair - two integers in the array have the same value, and two other integers // in the array have the same value // * One pair - two integers in the array have the same value // * Highest value - if none of the above hold true, the Highest Value in the array // is used to determine the result // // The method should evaluate the array and return back to the calling program a String // containing the score from the array of dice. // // EXTRA CREDIT: Include in your scoring a Straight, which is 5 numbers in sequence // [1,2,3,4,5] or [2,3,4,5,6] or [3,4,5,6,7] etc.. public static String getResult(int[] dice) { // Fill in the body } // Given an array of integers as input, return back an array with the counts of the // individual values in it. You may assume that all elements in the array will have // a value between 1 and 10. For example, if the array passed into the method were: // [1, 2, 3, 3, 7] // Then the array of counts returned back by this method would be: // [1, 1, 2, 0, 0, 0, 1, 0, 0, 0] // (Where index 0 holds the counts of the value 1, index 1 holds the counts of the value // 2, index 2 holds the counts of the value 3, etc.) // HINT: This method is very useful for determining the score of a particular hand // of poker dice. Use it as a helper method for the getResult() method above. public static int[] getCounts(int[] dice) { // Fill in the body } }

NOTE: To generate a random number between 1 and 10, use the Math.random() function as previously used in lab assignments. In this case, a random roll between 1 and 10 would be produced by this snippet of code: int roll = (int)(Math.random()*10)+1;

Project 10 Sample Output

This is a sample transcript of what your program should do. Items in bold are user input and should not be put on the screen by your program. Note that for full credit your output must be able to match the sample transcript's output EXACTLY for the same inputs - including spacing. In this project some of your output will be randomized so you can't replicate the transcript exactly in your tests - pay attention to the spacing for your submission. Your current dice: 4 2 1 4 6 Select a die to re-roll (-1 to keep remaining dice): 1 Your current dice: 4 0 1 4 6 Select a die to re-roll (-1 to keep remaining dice): 2 Your current dice: 4 0 0 4 6 Select a die to re-roll (-1 to keep remaining dice): 4 Your current dice: 4 0 0 4 0 Select a die to re-roll (-1 to keep remaining dice): -1 Keeping remaining dice... Rerolling... Your final dice: 4 2 3 4 6 One pair! Would you like to play again [Y/N]?: y Your current dice: 5 6 6 3 2 Select a die to re-roll (-1 to keep remaining dice): 0 Your current dice: 0 6 6 3 2 Select a die to re-roll (-1 to keep remaining dice): 3 Your current dice: 0 6 6 0 2 Select a die to re-roll (-1 to keep remaining dice): 4 Your current dice: 0 6 6 0 0 Select a die to re-roll (-1 to keep remaining dice): -1 Keeping remaining dice... Rerolling... Your final dice: 6 6 6 5 4 Three of a kind! Would you like to play again [Y/N]?: y Your current dice: 1 2 9 2 2 Select a die to re-roll (-1 to keep remaining dice): 0 Your current dice: 0 2 9 2 2 Select a die to re-roll (-1 to keep remaining dice): 2 Your current dice: 0 2 0 2 2 Select a die to re-roll (-1 to keep remaining dice): -1 Keeping remaining dice... Rerolling... Your final dice: 1 2 7 2 2 Three of a kind! Would you like to play again [Y/N]?: y Your current dice: 3 4 5 3 1 Select a die to re-roll (-1 to keep remaining dice): 0 Your current dice: 0 4 5 3 1 Select a die to re-roll (-1 to keep remaining dice): -1 Keeping remaining dice... Rerolling... Your final dice: 1 4 5 3 1 One pair! Would you like to play again [Y/N]?: n Goodbye! Note that your output depends on the choices made by the user. Remember to check that the user inputs a valid index for a die to re-roll (between 0 and 4, or -1 to quit) and that the user inputs either a Y or an N when asked to play again. The play again response should accept either capital or lower-case letters. A second transcript might look like this (note that this transcript implements the extra credit that allows you to score a Straight on this assignment) : Your current dice: 3 1 5 4 2 Select a die to re-roll (-1 to keep remaining dice): 6 Error: Index must be between 0 and 4 (-1 to quit)! Select a die to re-roll (-1 to keep remaining dice): -2 Error: Index must be between 0 and 4 (-1 to quit)! Select a die to re-roll (-1 to keep remaining dice): -1 Keeping remaining dice... Rerolling... Your final dice: 3 1 5 4 2 Straight! Would you like to play again [Y/N]?: Q ERROR! Only 'Y' or 'N' allowed as input! Would you like to play again [Y/N]?: q ERROR! Only 'Y' or 'N' allowed as input! Would you like to play again [Y/N]?: n Goodbye! HINT: Notice that the skeleton of code includes a method named getCounts() that provides an array of counts for each value in your dice set. A number that shows up 5 times will have a count of 5. A number that shows up 4 times will have a count of 4. Think about how these counts apply to all of the different possible combinations detailed above. EXTRA CREDIT HINT: It is easiest to figure out whether your dice are a Straight or not if you first put them into sorted order. For this you should research and use the Arrays.sort() method that exists in the standard Java library rather than coding your own sorting algorithm for this assignment.