Develop Reference

Updating Parameter Value in Java

I wasn't too sure what to title this so I apologize in advance. I am currently trying to make a game where the total points must add up to 100 for a player to win. I am running into the issue where the "PlayerTotalPoints" is not updating after the PlayerTurn method returns the amount of PlayerTotalPoints and sets that as the new value in PlayerTotalPoints to be rerun in the method once again.
This is my code:
public static void main(String[] args) {
int PlayerTotalPoints = 0;
int ComputerTotalPoints = 0;
while (!IsGameOver(PlayerTotalPoints, ComputerTotalPoints)) {
int TurnPointCounter = 0;
System.out.println("It is the player's turn!");
PlayerTotalPoints = PlayerTurn(TurnPointCounter, PlayerTotalPoints);
System.out.println("The player currently has " + PlayerTotalPoints + " total points!");
System.out.println("It is the computer's turn!");
ComputerTotalPoints = ComputerTurn(TurnPointCounter, ComputerTotalPoints);
System.out.println("The computer currently has " + ComputerTotalPoints + " total points!");
}
}
The method PlayerTurn returns the new value of the PlayerTotalPoints (I checked and it is returning the correct value of PlayerTotalPoints) but for some reason this value is not carrying over to the PlayerTotalPoints variable which needs to keep going as a player accumulates their score. This is for an assignment so I am not sure how much of my code I am allowed to share online but if you need more examples of my code just let me know, thanks.
EDIT: These are the PlayerTurn and ComputerTurn methods:
public static int PlayerTurn(int counter, int PlayerTotalPoints) {
System.out.println("The player currently has " + counter + " turn points.");
System.out.println("Do you want to play or hold this turn? (P/H)");
String answer = scan.nextLine();
answer = answer.replaceAll(" ", "");
answer = answer.toUpperCase();
if (answer.equals("H")) {
PlayerTotalPoints += counter;
System.out.println("You have elected to hold this turn.");
// System.out.println("You currently have " + PlayerTotalPoints + " total points.");
System.out.println(PlayerTotalPoints);
return PlayerTotalPoints;
}
int[] OneRoll = RollDice();
int TurnCount = Turn(OneRoll, counter);
if (OneRoll[0] == 6 && OneRoll[1] == 6) {
PlayerTotalPoints = 0;
return PlayerTotalPoints;
}
if (OneRoll[0] == 6 | OneRoll[1] == 6) {
// System.out.println("The player currently has " + PlayerTotalPoints + " total points.");
return PlayerTotalPoints;
}
PlayerTurn(TurnCount, PlayerTotalPoints);
return PlayerTotalPoints;
}
public static int ComputerTurn(int counter, int ComputerTotalPoints) {
System.out.println("The computer currently has " + counter + " turn points.");
int n = generator.nextInt(100);
if (n >= 70) {
ComputerTotalPoints += counter;
System.out.println("The computer has decided to hold this turn. ");
// System.out.println("The computer currently has " + ComputerTotalPoints + " total points.");
return ComputerTotalPoints;
}
int[] CompRoll = RollDice();
int CompTurnCount = Turn(CompRoll, counter);
if (CompRoll[0] == 6 && CompRoll[1] == 6) {
ComputerTotalPoints = 0;
return ComputerTotalPoints;
}
if (CompRoll[0] == 6 | CompRoll[1] == 6) {
// System.out.println("The computer currently has " + ComputerTotalPoints + " total points.");
return ComputerTotalPoints;
}
ComputerTurn(CompTurnCount, ComputerTotalPoints);
return ComputerTotalPoints;
}

Shouldn't the following:
PlayerTurn(TurnCount, PlayerTotalPoints);
return PlayerTotalPoints;
be something like
PlayerTotalPoints = PlayerTurn(TurnCount, PlayerTotalPoints);
return PlayerTotalPoints;
For both PlayerTurn and ComputerTurn method calls? Remember, this is a recursive call.

Why is my program looping twice more than needed?

I am completely new to programming and I was making a program for class. For the project, I need to make a "self directed" program. I wanted to make a simple program; I wanted a fighting simulator! So the point of the program is to do this:
Introduce you, and start the fight. The attack is completely random out of 5, and you and the "enemy" fight until one of you hits 0 hp. I want the program to end, and display the health of you and your enemy and tell you if you have won or not. Pretty simple, but it's harder than you'd think especially with the lack of programming I have learned. I just need help fixing it or simplifying it. Thanks for the information if you can help! Code below:
import java.util.Scanner;
public class TG_UN4EX13 {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String rumble = "startvalue";
System.out.println("Welcome to the Ultimate Battle Game!");
System.out.println("Have Fun!");
// Attack Section //
int attack1 = 5;
int attack2 = 10;
int attack3 = 20;
int attack4 = 40;
int cower = 0;
// Character Section//
int playerhealth = 100;
// Character Section//
// Enemy Section//
int enemyhealth = 100;
// Enemy Section//
while (playerhealth >= 0 || enemyhealth >= 0 || rumble.equalsIgnoreCase("Yes")) {
int attacknumber = (int) (Math.random() * (5 - 1 + 1) + 1);
int attacknumber2 = (int) (Math.random() * (5 - 1 + 1) + 1);
if (attacknumber == 1) {
enemyhealth = enemyhealth - attack1;
System.out.println("You used Punch!");
System.out.println("You did " + attack1 + " damage! \n");
} else if (attacknumber == 2) {
enemyhealth = enemyhealth - attack2;
System.out.println("You used Kick!");
System.out.println("You did " + attack2 + " damage! \n");
} else if (attacknumber == 3) {
enemyhealth = enemyhealth - attack3;
System.out.println("You used Jab!");
System.out.println("You did" + attack3 + " damage! \n");
} else if (attacknumber == 4) {
enemyhealth = enemyhealth - attack4;
System.out.println("You used Roundhouse Kick!");
System.out.println("You did " + attack4 + " damage! \n");
} else if (attacknumber == 5) {
enemyhealth = enemyhealth - cower;
System.out.println("You cowered in fear!");
System.out.println("You did " + cower + " damage! \n");
}
if (attacknumber2 == 1) {
playerhealth = playerhealth - attack1;
System.out.println("They used Punch!");
System.out.println("They did " + attack1 + " damage! \n");
} else if (attacknumber2 == 2) {
playerhealth = playerhealth - attack2;
System.out.println("They used Kick!");
System.out.println("They did " + attack2 + " damage! \n");
} else if (attacknumber2 == 3) {
playerhealth = playerhealth - attack3;
System.out.println("They used Jab!");
System.out.println("They did " + attack3 + " damage! \n");
} else if (attacknumber2 == 4) {
playerhealth = playerhealth - attack4;
System.out.println("They used Roundhouse Kick!");
System.out.println("They did " + attack4 + " damage! \n");
} else if (attacknumber2 == 5) {
playerhealth = playerhealth - cower;
System.out.println("They cowered in fear!");
System.out.println("They did " + cower + " damage! \n");
}
System.out.println("You have " + playerhealth + " health!");
System.out.println("They have " + enemyhealth + " health! \n");
}
if (playerhealth > enemyhealth) {
System.out.println("You won!");
System.out.println("Do you want to play again?");
rumble = scan.nextLine();
} else {
System.out.println("You lost!");
System.out.println("Do you want to play again?");
rumble = scan.nextLine();
}
if (rumble.equalsIgnoreCase("no")) {
System.out.println("Well, goodbye!");
System.exit(0);
}
}
}
P.S. This is a quick edit but here is an example:
You have 20 health! They have 20 health!
You used Jab! You did20 damage!
They used Roundhouse Kick! They did 40 damage!
You have -20 health! They have 0 health!
You used Jab! You did20 damage!
They used Roundhouse Kick! They did 40 damage!
You have -60 health! They have -20 health!
You lost! Do you want to play again?

I'm not positive, but I think you may need to change:
while(playerhealth>=0 || enemyhealth>=0 || rumble.equalsIgnoreCase("Yes"))
to
while((playerhealth>0 && enemyhealth>0) || rumble.equalsIgnoreCase("Yes"))
If the health is =0, it will run again, so remove the = as well

Take a look at the conditions for your loop.
while (playerhealth >= 0 || enemyhealth >= 0 || rumble.equalsIgnoreCase("Yes")) {
//do stuff
}
You're saying, "Keep fighting while any of the following conditions are true":
Player health is positive
Enemy health is positive
Rumble = Yes
Now think about what it will take to exit that loop (ie, end the game).
Exiting the loop is the opposite of staying in the loop, so you want the opposite of those conditions, which is, "Stop fighting when all of the following are true":
Player health is less than 0
Enemy health is less than 0
Rumble != Yes
Do you mean for the fight to only end when both the player and enemy have negative health, or should it end when either the player or the enemy have negative health?

Making a Pig Game using Object Oriented Programming (Java)

Hey guys so I made a Pig Game in Java for my CS project. I didn't have too much trouble with it because I only used one class. However, my professor now is making us implement OOP, and I'm having a lot of trouble. Here is my working Pig Game:
package edu.bsu.cs121.zmbarnes;
import java.util.Random;
import java.util.Scanner;
public class PigGame {
public static void main(String[] args) {
int player1TurnScore = 0;
int player1TotalScore = 0;
int player2TurnScore = 0;
int player2TotalScore = 0;
int dice;
int dice2;
String input = "r";
char repeat;
Scanner keyboard = new Scanner(System.in);
Random diceRoll = new Random();
System.out.println("Welcome to the game of Pig!\n");
while(player1TotalScore < 100 || player2TotalScore < 100){
// human's turn
System.out.println();
System.out.println("It is Player 1's turn.");
do{
dice = diceRoll.nextInt(6) + 1;
System.out.println("You rolled a " + dice);
if(dice == 1){
player1TurnScore = 0;
System.out.println("You lose your turn!");
System.out.println("Your total score is " + player1TotalScore);
break;
}else{
player1TurnScore += dice;
System.out.println("Your turn score is " + player1TurnScore);
System.out.println("And your total score is " + player1TotalScore);
System.out.println("If you hold, " + player1TurnScore + " points will be added to your total score.");
System.out.println("Enter 'r' to roll again, or 'h' to hold.");
input = keyboard.nextLine();
repeat = input.charAt(0);
if(repeat == 'h'){
break;
}
}
}while(input.equalsIgnoreCase("r") || dice != 1);
player1TotalScore += player1TurnScore;
System.out.println("Your score is " + player1TotalScore);
player1TurnScore = 0;
if(player1TotalScore >= 100){
System.out.println("Your total score is " + player1TotalScore);
System.out.println("PLAYER 1 WINS!");
break;
}
// Player 2's turn
System.out.println();
System.out.println("It is Player 2's turn.");
do{
dice2 = diceRoll.nextInt(6) + 1;
System.out.println("You rolled a " + dice2);
if(dice2 == 1){
player2TurnScore = 0;
System.out.println("You lose your turn!");
System.out.println("Your total score is " + player2TotalScore);
break;
}else{
player2TurnScore += dice2;
System.out.println("Your turn score is " + player2TurnScore);
System.out.println("And your total score is " + player2TotalScore);
System.out.println("If you hold, " + player2TurnScore + " points will be added to your total score.");
System.out.println("Enter 'r' to roll again, or 'h' to hold.");
input = keyboard.nextLine();
repeat = input.charAt(0);
if(repeat == 'h'){
break;
}
}
}while(input.equalsIgnoreCase("r") || dice2 != 1);
player2TotalScore += player2TurnScore;
System.out.println("Your score is " + player2TotalScore);
player2TurnScore = 0;
if(player2TotalScore >= 100){
System.out.println("Your total score is " + player2TotalScore);
System.out.println("PLAYER 2 WINS!");
break;
}
}
keyboard.close();
}
}
I must use a Dice class with a roll() method, a Player class with void takeTurn(), void bankPoints(), void makeChoice(), and boolean hasWon() methods, a GameOfPig class with , and Project class with void play() method, and the main Project class with main().
I'm just having trouble conceptualization how I can move my code into those methods so the game will work the exact same way. Any help would be appreciated!

I'm also new to OOD. My brief answer is highly borrowed from your code. I hope other one could correct me. Any suggestion is appreciated.
public class PigGame {
Dice dice;
Player player1;
Player player2;
public PigGame() {
this.player1 = new Player("Player1");
this.player2 = new Player("Player2");
this.dice = new Dice();
}
public void play() {
while (!player1.hasWon() && !player2.hasWon()) {
player1.takeTurn(dice);
if (!player1.hasWon())
player2.takeTurn(dice);
}
if (player1.hasWon()) {
System.out.println("Player1 won!");
} else {
System.out.println("Player2 won!");
}
}
public static void main(String[] args) {
PigGame pg = new PigGame();
pg.play();
}
}
class Dice {
private static Random diceRoll = new Random();
public int roll() {
return diceRoll.nextInt(6) + 1;
}
}
class Player {
private int currentRoundScore = 0;;
private int totalScore = 0;
private String playerName;
public Player(String name) {
this.playerName = name;
}
public void takeTurn(Dice dice) {
currentRoundScore = 0;
System.out.println("-------It's " + playerName + "'s turn.--------");
Scanner keyboard = new Scanner(System.in);
String input = "r";
int diceValue = 0;
do {
diceValue = dice.roll();
System.out.println("You rolled a " + diceValue);
if(diceValue == 1){
currentRoundScore = 0;
System.out.println("You lose your turn!");
System.out.println("Your total score is " + totalScore);
break;
}else{
currentRoundScore += diceValue;
System.out.println("Your turn score is " + currentRoundScore);
System.out.println("If you hold, " + currentRoundScore + " points will be added to your total score. And your total score would be " + currentRoundScore + totalScore);
System.out.println("Enter 'r' to roll again, or 'h' to hold.");
input = keyboard.nextLine();
char repeat = input.charAt(0);
if(repeat == 'h'){
break;
}
}
} while (input.equalsIgnoreCase("r") || diceValue != 1);
bankPoints();
}
public boolean hasWon() {
return totalScore >= 100;
}
public void bankPoints() {
totalScore += currentRoundScore;
System.out.println(playerName + "'s total score is " + totalScore + "\n");
}
}

Creating 1 decimal place

So I am more or less completely done with this code that runs a guessing game. At the end it prints the total results for all games played. This includes total games, total guesses, avg guesses/game and the best score. I have it all worked out except i need the avg guesses/game to show 1 decimal place but the System.out.printf("Guesses/game = %.1f") isn't working and idk why
import java.util.*; //so I can use scanner
public class GuessingGame {
public static void main(String[] args) {
Random rand = new Random ();
int max = 100;
Scanner input = new Scanner(System.in);
int guess;
boolean play = true;
int totalGames = 0;
int totalGuesses = 0;
int bestGame = Integer.MAX_VALUE;
System.out.println("Can you guess the word?");
System.out.println("I am sure you cannot guess!");
System.out.println("Go ahead and try!");
System.out.println();
while (play) { //repeats until user enters a statement besides y when asked to play again
System.out.println("I'm thinking of a number between 1 and " + max + "...");
int numberToGuess = rand.nextInt(max) + 1;
int numberOfTries = 0;
boolean win = false;
while (!win) {
System.out.print("Your guess? ");
guess = input.nextInt();
numberOfTries++;
if (guess == numberToGuess) {
win = true;
} else if (guess > numberToGuess) {
System.out.println("It's lower.");
} else if (guess < numberToGuess) {
System.out.println("It's higher.");
}
input.nextLine();
}
if (numberOfTries == 1) {
System.out.println("You got it right in " + numberOfTries + " guess!");
} else {
System.out.println("You got it right in " + numberOfTries + " guesses!");
}
totalGames++;
totalGuesses+= numberOfTries;
System.out.print("Do you want to play again? ");
String answer = input.nextLine();
char firstLetter = answer.charAt(0);
if (firstLetter == 'y' || firstLetter == 'Y') {
play = true;
} else {
play = false;
bestGame = Math.min(bestGame, numberOfTries);
}
System.out.println();
}
System.out.println("Overall results:");
System.out.println("Total games = " + totalGames);
System.out.println("Total guesses = " + totalGuesses);
System.out.printf("Guesses/game = ", totalGuesses/totalGames);
System.out.println("Best game = " + bestGame);
}
}

both totalGuesses and totalGames are integers, so when you divide them you get an integer, whereas %f needs a floating point number.
Instead cast one to a floating point number for floating point division:
totalGuesses/(double)totalGames

Try a decimal formatter if for some reason you're simply getting the wrong output:
DecimalFormat formatter = new DecimalFormat("#.#");
System.out.println(formatter.format(avgGuesses)); //or whatever your var name is

Java Lottery Array Program

I am designing a program for my class that is supposed to simulate a lottery game. I am supposed to design a method that generates random lottery numbers, a method that asks and stores the user for their number choices, a method that compares the arrays to find how many numbers are the same, and then I am supposed to call them all back up to the main method, and create my output statement that contains some if statements that determine which prize is awarded for the particular amount of matches.
Here is what I have thus far
import java.util.*;
public class LotteryGame {
/**
The main method is the program's starting point
*/
public static void main(String[] args){
int NUM_DIGITS = 5;
int[] userDigits = new int[5];
int[] lotteryNumbers = new int[5];
int sameNum;
generateNumbers(lotteryNumbers);
getUserData(userDigits);
compareArrays();
System.out.println("Lottery numbers: " + lotteryNumbers[0] + " " +
lotteryNumbers[1] + " " + lotteryNumbers[2] + " " + lotteryNumbers[3] +
" " + lotteryNumbers[4] + " ");
System.out.println("Player numbers: " + userDigits[0] + " " + userDigits[1] + " " + userDigits[2] + " " + userDigits[3] + " " + userDigits[4] + " ");
System.out.println("Number of matching digits: " + sameNum);
if (sameNum == 5){
System.out.println("GRAND PRIZE WINNER - $5 MILLION!!");
}
if (sameNum == 4){
System.out.println("SUPER PRIZE WINNER - $500,000!!");
}
if (sameNum == 3){
System.out.println("GOOD PRIZE WINNER - $5,000!!");
}
if (sameNum == 2){
System.out.println("NICE PRIZE WINNER - $500!!");
}
if (sameNum == 1){
System.out.println("WINNER - $5!!");
}
if (sameNum ==0){
System.out.println("No matching numbers - better luck next time");
}
}
public static int generateNumbers(int [] lotteryNumbers){
Random randNum = new Random();
lotteryNumbers[0] = randNum.nextInt(10);
lotteryNumbers[1] = randNum.nextInt(10);
lotteryNumbers[2] = randNum.nextInt(10);
lotteryNumbers[3] = randNum.nextInt(10);
lotteryNumbers[4] = randNum.nextInt(10);
return lotteryNumbers[4];
}
public static int getUserData (int [] userDigits){
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter digit 1: ");
userDigits[0] = keyboard.nextInt();
System.out.print("Enter digit 2: ");
userDigits[1] = keyboard.nextInt();
System.out.print("Enter digit 3: ");
userDigits[2] = keyboard.nextInt();
System.out.print("Enter digit 4: ");
userDigits[3] = keyboard.nextInt();
System.out.print("Enter digit 5: ");
userDigits[4] = keyboard.nextInt();
return userDigits[4];
}
public static int compareArrays (int [] userDigits,
int [] lotteryNumbers){
int sameNum = 0;
for (int i = 0; i < 5; i++){
for (int x = 0; x < 5; x++){
if (lotteryNumbers[i] == userDigits[x]){
sameNum++;
}
return sameNum;
}
return sameNum;
}
return sameNum;
}
}
I am very new to arrays (and Java at that) so my problems are in my return/call statements. Please excuse my spacey coding style and any blatant mistakes that I have made. Any tips,advice, solutions, or if you notice anything wrong with what I have please let me know. Thanks!

Keep in mind that randNum.nextInt(10) will give you lottery numbers that range from 0 to 9. You can use a for loop to assign the random numbers to the lotteryNumbers array easier. Also, you should make sure that the random lottery numbers don't repeat.
In your compareArrays function, just put one return sameNum call after the outermost for loop, otherwise it won't update with the correct number of matching numbers. You need to give compareArrays() the correct parameters (userDigits and lotteryNumbers) and set sameNum equal to this result.

Several points you might find useful:
You might want to use NUM_DIGITS for the initiation of the arrays since that's the whole point of having named constant:
int[] userDigits = new int[NUM_DIGITS];
int[] lotteryNumbers = new int[NUM_DIGITS];
You can use Arrays.toString() to output arrays, e.g.:
System.out.println(Arrays.toString(lotteryNumbers));
Instead of multiple ifs use switch, plus do not repeat the whole print statement, only assign the part that differs:
String prize = "";
switch (sameNum) {
case 5: prize = "GRAND PRIZE WINNER - $5 MILLION!!";
break;
case 4: prize = "SUPER PRIZE WINNER - $500,000!!";
break;
case 3: prize = "GOOD PRIZE WINNER - $5,000!!";
break;
case 2: prize = "NICE PRIZE WINNER - $500!!";
break;
case 1: prize = "WINNER - $5!!";
break;
case 0: prize = "No matching numbers - better luck next time";
break;
default: prize = "Something weird happened";
}
System.out.println(prize);

I've updated your code with the changes you'll need.
Added NUM_DIGITS to your initializer
Closed your Scanner
Removed the early returns in your comparison method
Assigned the return value of the comparison method to sameNum
Set the return value of the generation and get methods to void
The other suggestions might be something you want to incorporate (such as the switch/case).
import java.util.Random;
import java.util.Scanner;
public class App {
public static void main(String[] args) {
int NUM_DIGITS = 5;
int[] userDigits = new int[NUM_DIGITS];
int[] lotteryNumbers = new int[NUM_DIGITS];
int sameNum;
generateNumbers(lotteryNumbers);
getUserData(userDigits);
sameNum = compareArrays(lotteryNumbers, userDigits);
System.out.println("Lottery numbers: " + lotteryNumbers[0] + " "
+ lotteryNumbers[1] + " " + lotteryNumbers[2] + " "
+ lotteryNumbers[3] + " " + lotteryNumbers[4] + " ");
System.out.println("Player numbers: " + userDigits[0] + " "
+ userDigits[1] + " " + userDigits[2] + " " + userDigits[3]
+ " " + userDigits[4] + " ");
System.out.println("Number of matching digits: " + sameNum);
if (sameNum == 5) {
System.out.println("GRAND PRIZE WINNER - $5 MILLION!!");
}
if (sameNum == 4) {
System.out.println("SUPER PRIZE WINNER - $500,000!!");
}
if (sameNum == 3) {
System.out.println("GOOD PRIZE WINNER - $5,000!!");
}
if (sameNum == 2) {
System.out.println("NICE PRIZE WINNER - $500!!");
}
if (sameNum == 1) {
System.out.println("WINNER - $5!!");
}
if (sameNum == 0) {
System.out.println("No matching numbers - better luck next time");
}
}
public static void generateNumbers(int[] lotteryNumbers) {
Random randNum = new Random();
lotteryNumbers[0] = randNum.nextInt(10);
lotteryNumbers[1] = randNum.nextInt(10);
lotteryNumbers[2] = randNum.nextInt(10);
lotteryNumbers[3] = randNum.nextInt(10);
lotteryNumbers[4] = randNum.nextInt(10);
return lotteryNumbers[4];
}
public static void getUserData(int[] userDigits) {
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter digit 1: ");
userDigits[0] = keyboard.nextInt();
System.out.print("Enter digit 2: ");
userDigits[1] = keyboard.nextInt();
System.out.print("Enter digit 3: ");
userDigits[2] = keyboard.nextInt();
System.out.print("Enter digit 4: ");
userDigits[3] = keyboard.nextInt();
System.out.print("Enter digit 5: ");
userDigits[4] = keyboard.nextInt();
keyboard.close();
return userDigits[4];
}
public static int compareArrays(int[] userDigits, int[] lotteryNumbers) {
int sameNum = 0;
for (int i = 0; i < 5; i++) {
for (int x = 0; x < 5; x++) {
if (lotteryNumbers[i] == userDigits[x]) {
sameNum++;
}
}
}
return sameNum;
}
}