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Nested loop infinitely looping after random interval?

I am programming a connect 4 game using Java for an assignment. However, whenever player 2 makes a move about 5 moves in, the player 2 loop will infinitely loop. There is some sort of logic error that I cannot find, and it is frustrating. What is the logic error, and what is a good way to avoid future mistakes of the same vain?
I have tried changing the variables for the do > while loop where player 1 and player two attempt their moves. However that has no affect on it.
import java.util.Arrays;
public class Lab6Shell {
public static void main(String args[]) {
// variables
Scanner input = new Scanner(System.in);
char[][] board = new char[7][8];
boolean finished = false;
boolean gameOver = false;
int width = 7;
int height = 8;
char currentPlayer = 'X';
int numMoves = 0;
int bottom_row = width - 1;
// loop until user wants to stop
for (int row = 0; row < board.length; row++) {
java.util.Arrays.fill(board[row], 0, board[row].length, '*');
}
do {
// display the board
DisplayBoard(board);
// loop until this game is over
do {
// get the next move for the current player
int columnChosen = 0;
do {
if (currentPlayer == 'X') {
int counter = 1;
System.out.println("Player 1 turn");
System.out.println("Enter the column you want to place your piece.");
columnChosen = input.nextInt();
input.nextLine();
while (true) {
if (columnChosen > width) {
System.out.println("That's not a valid column");
break;
}
if ((board[bottom_row][columnChosen] == '*')) {
board[bottom_row][columnChosen] = 'X';
break;
} else if ((board[bottom_row][columnChosen] == 'X')
|| (board[bottom_row][columnChosen] == 'O')) {
if (board[bottom_row - counter][columnChosen] == '*') { // puts X if blank
board[bottom_row - counter][columnChosen] = 'X';
break;
}
counter += 1;
if (counter == width) {
System.out.println("That column is full");
break;
}
}
}
}
if (currentPlayer == 'O') {
int counter = 1;
System.out.println("Player 2's turn");
System.out.println("Enter the column you want to place your piece.");
columnChosen = input.nextInt();
input.nextLine();
while (true) {
if (columnChosen > width) {
System.out.println("That's not a valid column");
break;
}
if ((board[bottom_row][columnChosen] == '*')) {
board[bottom_row][columnChosen] = 'O';
break;
} else if ((board[bottom_row][columnChosen] == 'X')
|| (board[bottom_row][columnChosen] == 'O')) {
if (board[bottom_row - counter][columnChosen] == '*') { // puts O
board[bottom_row - counter][columnChosen] = 'O';
break;
}
counter += 1;
if (counter == width) {
System.out.println("That column is full");
break;
}
}
}
}
} while (columnChosen < 0 || columnChosen > 8 || board[1][columnChosen] != '*');
// place piece
// increment number of moves
numMoves++;
// display the board
DisplayBoard(board);
// check for win
if (checkWin(board)) {
// if winner, display congratulations and set gameOver true
System.out.println("Congratulations! You won!");
gameOver = true;
} else if (numMoves == 42) {
// if tie, display result and set gameOver true
DisplayBoard(board);
System.out.println("Tie Game! Game over");
gameOver = true;
} else if (checkWin(board) == false) {
if (currentPlayer == ('X')) {
currentPlayer = ('O');
} else {
currentPlayer = ('X');
}
}
} while (!gameOver);
// ask if user wants to play again, set finished accordingly
System.out.println("Would you like to play again?");
input.nextLine();
String decision = input.nextLine();
if (decision.toLowerCase().equals("yes")) {
finished = false;
}
else if (decision.toLowerCase().equals("no")) {
finished = true;
}
} while (finished == false);
}
// this method displays the board passed in
public static void DisplayBoard(char[][] board) {
for (int i = 0; i < board.length; i++) {
System.out.print("|");
for (int j = 0; j < board[i].length; j++) {
System.out.print(" " + board[i][j] + "|");
}
System.out.println("");
}
}
public static boolean checkWin(char[][] board) {
final int HEIGHT = board.length;
final int WIDTH = board[0].length;
final int EMPTY_SLOT = '*';
for (int r = 0; r < HEIGHT; r++) { // iterate rows, bottom to top
for (int c = 0; c < WIDTH; c++) { // iterate columns, left to right
char player = board[r][c];
if (player == EMPTY_SLOT)
continue; // don't check empty slots
if (c + 3 < WIDTH && player == board[r][c + 1] && // look right
player == board[r][c + 2] && player == board[r][c + 3])
return true;
if (r + 3 < HEIGHT) {
if (player == board[r + 1][c] && // look up
player == board[r + 2][c] && player == board[r + 3][c])
return true;
if (c + 3 < WIDTH && player == board[r + 1][c + 1] && // look up & right
player == board[r + 2][c + 2] && player == board[r + 3][c + 3])
return true;
if (c - 3 >= 0 && player == board[r + 1][c - 1] && // look up & left
player == board[r + 2][c - 2] && player == board[r + 3][c - 3])
return true;
}
}
}
return false; // no winner found
}
}
The expected result is that each player will play a piece until four of the same piece are in a row. Then the first to reach four in a row is declared the winner, and the game ends. However, once the game gets in about 5 loops, the player 2 loop infinitely loops until a column is full, and does not print out the board.

Your infinite loop is caused by checking the condition board[1][columnChosen] != '*' in your do ... while loop. The program will continue to ask the current user for a new move as long as the second to top row of the selected column is occupied.
Replace:
do
{
...
} while (columnChosen < 0 || columnChosen > 8 || board[1][columnChosen] != '*');
With:
do
{
...
} while (columnChosen < 0 || columnChosen > 8)
This should get you to a point where you can tackle the remaining issues.

Connect four - finding the winning Processing (Java)

I'm building a connect 4 game using Processing (Java) and have come to a holt when trying to find the winner. I've posted the code could anyway tell me why this isn't working? or how I would remedy it.
Any help is greatly appreciated.
Thanks
if (whooseWon() == true) {
text = loadFont("Tahoma-Bold-50.vlw");
textFont(text, 50);
fill(255, 0, 0);
game = false;
if (whoWon == 1) {
text("Red Wins!", width/4, height/4);
text("Click to play again", 110, height/2);
} else if (whoWon == 2) {
fill(255, 255, 0);
text("yellow Wins!", width/4, height/4);
text("Click to play again", 110, height/2);
} else if (whoWon == 3) {
fill(255, 255, 0);
text("It's a Tie", width/4, height/4);
text("Click to play again", 110, height/2);
}
}
}
// click to play again functionality
void mousePressed() {
if (game == false) {
game = true;
setup();
}
}
// 21 vertical possibilities, 24 horizontal and 12 diagonally that's a total of 69 possibilities
// cols = j
// rows = i
boolean whooseWon() {
// horizontal
for (int i = 0; i < rows-3; i++) {
for (int j = 0; j < cols; j++) {
//red player
if (piece[i+1][j].getColour() == color(counter1) && piece[i+1]. [j].getColour() == color(counter1) &&
piece[i+2][j].getColour() == color(counter1) && piece[i+3][j].getColour() == color(counter1))
{
whoWon = 1;
return true;
}
if (piece[i][j].getColour() == color(counter2) && piece[i+1][j].getColour() == color(counter2) &&
piece[i+2][j].getColour() == color(counter2) && piece[i+3][j].getColour() == color(counter2))
{
whoWon = 2;
return true;
}
}
}
// vertical
for (int i = 0; i < rows; i++) {
for (int j = 0; j < cols-3; j++) {
//red player
if (piece[i][j].getColour() == color(counter1) && piece[i][j+1].getColour() == color(counter1) &&
piece[i][j+2].getColour() == color(counter1) && piece[i][j+3].getColour() == color(counter1))
{
whoWon = 1;
return true;
}
if (piece[i][j].getColour() == color(counter2) && piece[i][j+1].getColour() == color(counter2) &&
piece[i][j+2].getColour() == color(counter2) && piece[i][j+3].getColour() == color(counter2))
{
whoWon = 2;
return true;
}
}
}
//diagonal
for (int i = 0; i < rows-3; i++) {
for (int j = 0; j < cols-3; j++) {
//red player
if (piece[i][j].getColour() == color(counter1) && piece[i+1][j+1].getColour() == color(counter1) &&
piece[i+2][j+2].getColour() == color(counter1) && piece[i+3][j+3].getColour() == color(counter1))
{
whoWon = 1;
return true;
}
if (piece[i][j].getColour() == color(counter2) && piece[i+1][j+1].getColour() == color(counter2) &&
piece[i+2][j+2].getColour() == color(counter2) && piece[i+3][j+3].getColour() == color(counter2))
{
whoWon = 2;
return true;
}
}
}
//diagonal
for (int i = 0; i < rows-3; i++) {
for (int j = 0; j < cols; j++) {
//red player
if (piece[i][j].getColour() == color(counter2) && piece[i+1]
[j-1].getColour() == color(counter2) &&
piece[i+2][j-2].getColour() == color(counter2) && piece[i+3]
[j-3].getColour() == color(counter2))
{
whoWon = 1;
return true;
}
if (piece[i][j].getColour() == color(counter2) && piece[i+1]. [j+1].getColour() == color(counter2) &&
piece[i+2][j-2].getColour() == color(counter2) && piece[i+3]
[j-3].getColour() == color(counter2))
{
whoWon = 2;
return true;
}
}
}
return false;
}
`

You're making it pretty hard for people to help you. Instead of posting a disconnected snippet from your huge sketch, try to create an MCVE. This usually involves starting over with a blank sketch and only adding enough code to repeat the problem, without any of the extra stuff not directly related to it. We should be able to copy and paste the code into our own editors, hit run, and see the same thing as you. Otherwise we're all just guessing. You'll often solve your problem in the process of creating an MCVE!
That being said, I can help you try to debug your problem. You've said that you're getting an ArrayIndexOutOfBounds exception. Which line is the error on? I'm not asking that so you tell me. I'm asking that because it's the first question you should be asking yourself.
When you get it narrowed down to a specific line, then you need to backtrack to find out exactly what's going on. What indexes are being accessed? How many indexes do the arrays have? You've got a mismatch between the two, which is causing your problem.
Use the println() function to print out every value that might be part of this. That's at least the i and j variables, as well as row and columns, and piece.length and piece[yourIndexHere].length.
Then walk through your code line-by-line until you understand exactly what it's doing. Again, you'll have much better luck if you work from an MCVE instead of trying to parse through a big mess. Then if you get stuck, you can post a new question with that MCVE and it'll be much easier for us to help you. Good luck.

Minimax algorithm in 4x4 TicTacToe board

I'm working in artificial intelligence project to develop a TicTacToe 4X4 using Minimax algorithm
I have this existing program that run Minimax algorithm in 3x3 TicTacToe board.
I want to extend it to 4x4 TicTacToe
but I couldn't any idea how I can do it ??
import java.util.*;
//defines the point where to place 1 or 2
class Point {
int x, y;
public Point(int x, int y) {
this.x = x;
this.y = y;
}
#Override
public String toString() {
return "[" + x + ", " + y + "]";
}
}
//defines the score per point -1,0,1
class PointsAndScores {
int score;
Point point;
PointsAndScores(int score, Point point) {
this.score = score;
this.point = point;
}
}
//defince the game board
class Board {
List<Point> availablePoints;
Scanner scan = new Scanner(System.in);
int[][] board = new int[3][3];
public Board() {
}
public boolean isGameOver() {
//Game is over is someone has won, or board is full (draw)
return (hasXWon() || hasOWon() || getAvailableStates().isEmpty());
}
//check if X have won represented by 1
public boolean hasXWon() {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 1) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 1)) {
//System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < 3; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 1)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 1))) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
//check if O has won represented by 2
public boolean hasOWon() {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 2) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 2)) {
// System.out.println("X Diagonal Win");
return true;
}
for (int i = 0; i < 3; ++i) {
if ((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 2)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 2)) {
// System.out.println("X Row or Column win");
return true;
}
}
return false;
}
//check available states in the board
public List<Point> getAvailableStates() {
availablePoints = new ArrayList<>();
for (int i = 0; i < 3; ++i) {
for (int j = 0; j < 3; ++j) {
if (board[i][j] == 0) {
availablePoints.add(new Point(i, j));
}
}
}
return availablePoints;
}
//put player move in the board
public void placeAMove(Point point, int player) {
board[point.x][point.y] = player; //player = 1 for O, 2 for X..
}
//get best movement according to the board state
public Point returnBestMove() {
int MAX = -100000;
int best = -1;
for (int i = 0; i < rootsChildrenScores.size(); ++i) {
if (MAX < rootsChildrenScores.get(i).score) {
MAX = rootsChildrenScores.get(i).score;
best = i;
}
}
return rootsChildrenScores.get(best).point;
}
//accepts input from user
void takeHumanInput() {
System.out.println("Your move: ");
int x = scan.nextInt();
int y = scan.nextInt();
Point point = new Point(x, y);
placeAMove(point, 2);
}
//display current board
public void displayBoard() {
System.out.println();
for (int i = 0; i < 3; ++i) {
for (int j = 0; j < 3; ++j) {
System.out.print(board[i][j] + " ");
}
System.out.println();
}
}
//get min value
public int returnMin(List<Integer> list) {
int min = Integer.MAX_VALUE;
int index = -1;
for (int i = 0; i < list.size(); ++i) {
if (list.get(i) < min) {
min = list.get(i);
index = i;
}
}
return list.get(index);
}
//get max value
public int returnMax(List<Integer> list) {
int max = Integer.MIN_VALUE;
int index = -1;
for (int i = 0; i < list.size(); ++i) {
if (list.get(i) > max) {
max = list.get(i);
index = i;
}
}
return list.get(index);
}
//declares a list for scores
List<PointsAndScores> rootsChildrenScores;
//excutes minimax algorithm
public void callMinimax(int depth, int turn){
rootsChildrenScores = new ArrayList<>();
minimax(depth, turn);
}
//minimax algorithm
public int minimax(int depth, int turn) {
if (hasXWon()) return +1;
if (hasOWon()) return -1;
//get available states from the board
List<Point> pointsAvailable = getAvailableStates();
if (pointsAvailable.isEmpty()) return 0;
//stores scores
List<Integer> scores = new ArrayList<>();
for (int i = 0; i < pointsAvailable.size(); ++i) {
Point point = pointsAvailable.get(i);
if (turn == 1) { //O's turn select the highest from below minimax() call
placeAMove(point, 1);
int currentScore = minimax(depth + 1, 2);
scores.add(currentScore);//add scores to the list
if (depth == 0)
rootsChildrenScores.add(new PointsAndScores(currentScore, point));
} else if (turn == 2) {//X's turn select the lowest from below minimax() call
placeAMove(point, 2);
scores.add(minimax(depth + 1, 1));
}
board[point.x][point.y] = 0; //Reset this point
}
return turn == 1 ? returnMax(scores) : returnMin(scores);
}
}
//main class
public class TicTacToe {
public static void main(String[] args) {
Board b = new Board();//instantiate board
Random rand = new Random();//instantiate random value
b.displayBoard();//display board
System.out.println("Who's gonna move first? (1)Computer (2)User: ");
int choice = b.scan.nextInt();
if(choice == 1){
Point p = new Point(rand.nextInt(3), rand.nextInt(3));
b.placeAMove(p, 1);
b.displayBoard();
}
while (!b.isGameOver()) {
System.out.println("Your move: ");
Point userMove = new Point(b.scan.nextInt(), b.scan.nextInt());
b.placeAMove(userMove, 2); //2 for X and X is the user
b.displayBoard();
if (b.isGameOver()) {
break;
}
b.callMinimax(0, 1);
for (PointsAndScores pas : b.rootsChildrenScores) {
System.out.println("Point: " + pas.point + " Score: " + pas.score);
}
b.placeAMove(b.returnBestMove(), 1);
b.displayBoard();
}
if (b.hasXWon()) {
System.out.println("Unfortunately, you lost!");
} else if (b.hasOWon()) {
System.out.println("You win! This is not going to get printed.");
} else {
System.out.println("It's a draw!");
}
}
}

You need to introduce an integer variable, let's say n, which will contain the size of the board(i.e. # of cells = n*n). Before a game starts, the player will be asked for the preferred board size, 3 or 4, and the corresponding board will be created. In order for your program to work with 4x4 like it did with 3x3, we will need to place the variable n wherever we have a method or loop that needs to traverse through the board. In other words, instead of 3 we will place n. This will "generalize" our program. For example, within the display method we have 2 for loops that run as long as i and j are smaller than 3. To "generalize" our program to a semi-arbitrary board size(3 or 4), we place an n in place of the 3 so that the loop will run as long as i and j are smaller than n(3 or 4). This change from 3 to n will apply wherever we have a 3 that indicates the size of the board. Another thing we will need to change are the checking methods hasXWon() and hasOWon(). Here, we will need to add an extra section for when the board size is 4 and not 3. This will look more or less the same as it's counterpart with the only difference being that it will check the extra row, column and longer diagonals that exist in a 4x4 board. After inserting these changes, the program now looks like this:
import java.util.*;
//defines the point where to place 1 or 2
class Point {
int x, y;
public Point(int x, int y) {
this.x = x;
this.y = y;
}
#Override
public String toString() {
return "[" + x + ", " + y + "]";
}
}
//defines the score per point -1,0,1
class PointsAndScores {
int score;
Point point;
PointsAndScores(int score, Point point) {
this.score = score;
this.point = point;
}
}
//defince the game board
class board {
List<Point> availablePoints;
Scanner scan = new Scanner(System.in);
public int n;
int[][] board;
public board(int n) {
this.n = n;
board = new int[n][n];
}
public boolean isGameOver() {
//Game is over is someone has won, or board is full (draw)
return (hasXWon() || hasOWon() || getAvailableStates().isEmpty());
}
//check if X have won represented by 1
public boolean hasXWon() {
if(n==3){
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 1) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 1)) {
//System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < n; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 1)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 1))) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
else {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == board[3][3]&& board[0][0] == 1) || (board[0][3] == board[1][2] && board[0][3] == board[2][1] && board[0][3] == board[3][0] && board[0][3] == 1)) {
//System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < n; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 1)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 1))) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
}
//check if O has won represented by 2
public boolean hasOWon() {
if(n==3){
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 2) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 2)) {
//System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < n; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 2)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 2))) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
else {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == board[3][3]&& board[0][0] == 2) || (board[0][3] == board[1][2] && board[0][3] == board[2][1] && board[0][3] == board[3][0] && board[0][3] == 2)) {
//System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < n; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 2)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 2))) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
}
//check available states in the board
public List<Point> getAvailableStates() {
availablePoints = new ArrayList<>();
for (int i = 0; i < n; ++i) {
for (int j = 0; j < n; ++j) {
if (board[i][j] == 0) {
availablePoints.add(new Point(i, j));
}
}
}
return availablePoints;
}
//put player move in the board
public void placeAMove(Point point, int player) {
board[point.x][point.y] = player; //player = 1 for O, 2 for X..
}
//get best movement according to the board state
public Point returnBestMove() {
int MAX = -100000;
int best = -1;
for (int i = 0; i < rootsChildrenScores.size(); ++i) {
if (MAX < rootsChildrenScores.get(i).score) {
MAX = rootsChildrenScores.get(i).score;
best = i;
}
}
return rootsChildrenScores.get(best).point;
}
//accepts input from user
void takeHumanInput() {
System.out.println("Your move: ");
int x = scan.nextInt();
int y = scan.nextInt();
Point point = new Point(x, y);
placeAMove(point, 2);
}
//display current board
public void displayboard() {
System.out.println();
for (int i = 0; i < n; ++i) {
for (int j = 0; j < n; ++j) {
System.out.print(board[i][j] + " ");
}
System.out.println();
}
}
//get min value
public int returnMin(List<Integer> list) {
int min = Integer.MAX_VALUE;
int index = -1;
for (int i = 0; i < list.size(); ++i) {
if (list.get(i) < min) {
min = list.get(i);
index = i;
}
}
return list.get(index);
}
//get max value
public int returnMax(List<Integer> list) {
int max = Integer.MIN_VALUE;
int index = -1;
for (int i = 0; i < list.size(); ++i) {
if (list.get(i) > max) {
max = list.get(i);
index = i;
}
}
return list.get(index);
}
//declares a list for scores
List<PointsAndScores> rootsChildrenScores;
//excutes minimax algorithm
public void callMinimax(int depth, int turn){
rootsChildrenScores = new ArrayList<>();
minimax(depth, turn);
}
//minimax algorithm
public int minimax(int depth, int turn) {
if (hasXWon()) return +1;
if (hasOWon()) return -1;
//get available states from the board
List<Point> pointsAvailable = getAvailableStates();
if (pointsAvailable.isEmpty()) return 0;
//stores scores
List<Integer> scores = new ArrayList<>();
for (int i = 0; i < pointsAvailable.size(); ++i) {
Point point = pointsAvailable.get(i);
if (turn == 1) { //O's turn select the highest from below minimax() call
placeAMove(point, 1);
int currentScore = minimax(depth + 1, 2);
scores.add(currentScore);//add scores to the list
if (depth == 0)
rootsChildrenScores.add(new PointsAndScores(currentScore, point));
} else if (turn == 2) {//X's turn select the lowest from below minimax() call
placeAMove(point, 2);
scores.add(minimax(depth + 1, 1));
}
board[point.x][point.y] = 0; //Reset this point
}
return turn == 1 ? returnMax(scores) : returnMin(scores);
}
}
//main class
public class TicTacToe {
public static void main(String[] args) {
//board b = new board();//instantiate board
Random rand = new Random();//instantiate random value
Point p;
Scanner s = new Scanner(System.in);
System.out.println("Choose board size: 3 or 4?");
int n=s.nextInt();
board b = new board(n); //Instantiating board after value of n has been read. This is important because the value of n is required for the instantiation to take place.
System.out.println(b.n);
b.displayboard();//display board
System.out.println("Who's gonna move first? (1)Computer (2)User: ");
int choice = b.scan.nextInt();
if(choice == 1){
if(b.n==3)
p = new Point(rand.nextInt(3), rand.nextInt(3));
else
p = new Point(rand.nextInt(4), rand.nextInt(4));
b.placeAMove(p, 1);
b.displayboard();
}
while (!b.isGameOver()) {
System.out.println("Your move: ");
Point userMove = new Point(b.scan.nextInt(), b.scan.nextInt());
b.placeAMove(userMove, 2); //2 for X and X is the user
b.displayboard();
if (b.isGameOver()) {
break;
}
b.callMinimax(0, 1);
for (PointsAndScores pas : b.rootsChildrenScores) {
System.out.println("Point: " + pas.point + " Score: " + pas.score);
}
b.placeAMove(b.returnBestMove(), 1);
b.displayboard();
}
if (b.hasXWon()) {
System.out.println("Unfortunately, you lost!");
} else if (b.hasOWon()) {
System.out.println("You win! This is not going to get printed.");
} else {
System.out.println("It's a draw!");
}
}
}
Your program is now able to create 4x4 games. There are however two things that you need to do. First, your placeAMove(...) method doesn't check if a cell is occupied before filling it. This may lead to cells being overwritten, so you must change that by checking if a cell is occupied before trying to fill it. The second and more important thing is that although the program is now able to create 4x4 games, it will not be able to carryout a proper game. The reason for this is that the number of nodes(states) created by minimax to find the next move, although manageable in 3x3 games, rises dramatically for 4x4 games. This means that it would take your computer A LOT of time, and by a lot I mean hours, to calculate the computer's second move. Even when I rigged the game(i.e. manually inserted random 1s and 2s in the cells before allowing minimax to be called to choose the computer's move) it still took the computer over 30 seconds to calculate it's move. This renders your game, of course, unplayable in 4x4 mode. There are, of course, ways, such as Memoization or Alpha-Beta Pruning or both together, to overcome this and speed up your algorithm. Here is a previously asked question to get you started on these topics. The chess programming wiki is also a good source of information on such topics, if a bit more complex in it's structure. Here's their entry on Memoization(Here called transposition tables).

How to keep track of winner in Connect Four Java game

This is a class that creates the game connect four in console and drawing panel, and I am having trouble in the connectedFour method where it determines if someone has gotten 4 discs in a row. The problem is, is that I am not sure how to set up my for loops to check through the array for four discs in a row
Here is my code:
import java.util.*;
import java.awt.*;
public class ConnectFour{
public static void main(String[] args){
//board
DrawingPanel panel = new DrawingPanel(550,550);
int rowAvailable;
Graphics g = panel.getGraphics();
g.drawLine(0,0,0,500);
g.drawLine(0,0,500,0);
g.drawLine(500,0,500,427);
g.drawLine(0,427,500,427);
for(int i = 0; i< 6; i++){
for(int j= 0; j<= 6; j++){
g.setColor(Color.YELLOW);
g.fillRect(j*71,i*71,71,71);
g.setColor(Color.WHITE);
g.fillOval(j*71,i*71,71,71);
}
}
//setBlankArray
Scanner console = new Scanner(System.in);
char[][] board = new char[6][7];
for(int j = 0;j <= 6; j++){
for(int i= 0; i < 6; i++){
board[i][j] = ' ';
}
}
boolean isBlack = true;
boolean isRed = false;
int column = 0;
boolean playersTurn = true;
boolean rightNum = false;
//oneTurn
while(getWinner(board, playersTurn)){
//while(playersTurn == true){
rightNum = false;
if(isBlack == true){
// displayCurrentPlayer
System.out.println("Black's Turn");
g.setColor(Color.WHITE);
g.drawString("Red Disc's Turn",200, 450);
g.setColor(Color.BLACK);
g.drawString("Black Disc's Turn",200, 450);
}
else{
// displayCurrentPlayer
System.out.println("Red's Turn");
g.setColor(Color.WHITE);
g.drawString("Black Disc's Turn",200, 450);
g.setColor(Color.RED);
g.drawString("Red Disc's Turn",200, 450);
}
System.out.print("Choose a column to place your disk (1-7): ");
while(rightNum == false){
column = (console.nextInt()) -1;
if(column >= 0 && column < 7 && board[0][column] == ' '){
rightNum = true;
}
else{
System.out.print("Try again: ");
}
}
drawBoard(column, board, isBlack, isRed, board, g);
isBlack = !isBlack;
}
if(isBlack == false){System.out.println("Congratulations Black Player");}
else{System.out.println("Congratulations Red Player");}
// use the while loop to say try again if the column is filled.
}
public static void drawBoard(int column, char[][] board, boolean isBlack, boolean isRed, char[][] availability,Graphics g){
char player = ' ';
if(isBlack == true){
g.setColor(Color.BLACK);
player = 'b';
}
else{
g.setColor(Color.RED);
player = 'r';
}
int x = 0;
int row = 5;
while(board[row-x][column] != ' '){
x++;
}
row = row-x;
g.fillOval((column * 71),(row * 71), 71,71);
board[row][column] = player;
}
public static boolean getWinner(char[][] board, boolean playersTurn){
int verticalCount = 0;
boolean isVertical = false;
for(int i = 6; i >= 0; i--){
verticalCount = 0;
for(int j = 5; j > 0; j--){
if(board[j][i] == board[j-1][i] && board[j][i] != ' '){
verticalCount++;
}
if(verticalCount == 4){
isVertical = true;
}
}
}
int horizontalCount = 0;
boolean isHorizontal = false;
for(int i =1; i <= 5; i++){
for(int j =1; j<6; j++){
if(board[j][i] == board[j][i+1] && board[j][i] != ' '){
horizontalCount++;
}
if(horizontalCount == 3){
isHorizontal = true;
}
}
}
int diagonalCount = 0;
boolean isDiagonal = false;
// for(int i = 0; i<=6; i++){
// for(int j =0; j<6; j++){
// if(board[i][j-1] == board[i][j]){
// diagonalCount++;
// }
// }
// }
if(isVertical || isHorizontal || isDiagonal){
playersTurn = false;
}
else{
playersTurn = true;}
return playersTurn;
}
}

I would implement this by checking if the game-winning condition is met after a disc has been placed. This way you aren't iterating over the entire board after each move.
Regardless, try this:
replace
while (gameWon == false ){
with
while (!connectedFour(board, playersTurn)) {
I don't think this will completely fix your problems as it looks like there are a handful of other things wrong with the code you've posted.

Connect Four Win Check Not Working

So I have been working on my final term project which is a Connect Four game. I ran into this issue where i believe my CheckWin logic should work, put is providing me with no output when i run the program. I have my CheckWin() being called in my actionPerformed and I am stuck as to what to do here. As a side note, is there any way to easily increase the size of text inside of a JButton? I would like to increase the size of the "X's" and "O's". I am relatively new at programming so sorry if these are simple fixes. My code is below:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Connect implements ActionListener {
private JFrame window = new JFrame();
private JPanel myPanel = new JPanel();
private JPanel myPanelB = new JPanel();
private JButton[][] myButtons = new JButton[6][7];
private JButton[] buttons = new JButton[7];
private boolean win = false;
private int count = 5;
private int count2 = 5;
private int count3 = 5;
private int count4 = 5;
private int count5 = 5;
private int count6 = 5;
private int count7 = 5;
private int countA = 0;
private String letter = "";
public boolean checkHorizontalWin(String letter) {
for (int y = 0; y < myButtons.length; y++) {
// going to length-3 to avoid IndexOutOfBounds exception
for (int x = 0; x < myButtons[y].length - 3; x++) {
if (myButtons[y][x].getText().equals(letter)
&& myButtons[y][x + 1].getText().equals(letter)
&& myButtons[y][x + 2].getText().equals(letter)
&& myButtons[y][x + 3].getText().equals(letter)
) {
return true;
}
}
}
return false;
}
public boolean checkVerticalWin(String letter) {
for (int y = 0; y < myButtons.length - 3; y++) {
for (int x = 0; x < myButtons[y].length; x++) {
if (myButtons[y][x].getText().equals(letter)
&& myButtons[y + 1][x].getText().equals(letter)
&& myButtons[y + 2][x].getText().equals(letter)
&& myButtons[y + 3][x].getText().equals(letter)
) {
return true;
}
}
}
return false;
}
public boolean checkDiagonalToTheLeftWin(String letter) {
for (int y = 0; y < myButtons.length - 3; y++) {
for (int x = 0; x < myButtons[y].length - 3; x++) {
if (myButtons[y][x].getText().equals(letter)
&& myButtons[y + 1][x + 1].getText().equals(letter)
&& myButtons[y + 2][x + 2].getText().equals(letter)
&& myButtons[y + 3][x + 3].getText().equals(letter)
) {
return true;
}
}
}
return false;
}
public boolean checkDiagonalToTheRightWin(String letter) {
for (int y = 0; y < myButtons.length - 3; y++) {
for (int x = 3; x < myButtons[y].length; x++) {
if (myButtons[y][x].getText().equals(letter)
&& myButtons[y + 1][x - 1].getText().equals(letter)
&& myButtons[y + 2][x - 2].getText().equals(letter)
&& myButtons[y + 3][x - 3].getText().equals(letter)
) {
return true;
}
}
}
return false;
}
public Connect(){
window.setSize(800,700);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myPanel.setLayout(new GridLayout(1,7));
myPanelB.setLayout(new GridLayout(6,7));
for (int i = 0; i < buttons.length; i ++){
buttons[i] = new JButton();
myPanel.add(buttons[i]);
buttons[i].addActionListener(this);
}
for (int i = 0; i < 6; i ++){
for (int j = 0; j < 7; j ++){
myButtons[i][j] = new JButton();
myPanelB.add(myButtons[i][j]);
}
}
window.add(myPanel, BorderLayout.NORTH);
window.add(myPanelB, BorderLayout.CENTER);
window.setVisible(true);
}
public void actionPerformed(ActionEvent e){
countA++;
if (countA % 2 == 0)
letter = "X";
else
letter = "O";
if (e.getSource() == buttons[0]){
myButtons[count][0].setText(letter);
count --;
}
if (e.getSource() == buttons[1]){
myButtons[count2][1].setText(letter);
count2 --;
}
if (e.getSource() == buttons[2]){
myButtons[count3][2].setText(letter);
count3--;
}
if (e.getSource() == buttons[3]){
myButtons[count4][3].setText(letter);
count4--;
}
if (e.getSource() == buttons[4]){
myButtons[count5][4].setText(letter);
count5--;
}
if (e.getSource() == buttons[5]){
myButtons[count6][5].setText(letter);
count6--;
}
if (e.getSource() == buttons[6]){
myButtons[count7][6].setText(letter);
count7--;
}
if (myButtons[0][0].getText().equals("O") || myButtons[0][0].getText().equals("X")){
buttons[0].setEnabled(false);
}
if (myButtons[0][1].getText().equals("O") || myButtons[0][1].getText().equals("X")){
buttons[1].setEnabled(false);
}
if (myButtons[0][2].getText().equals("O") || myButtons[0][2].getText().equals("X")){
buttons[2].setEnabled(false);
}
if (myButtons[0][3].getText().equals("O") || myButtons[0][3].getText().equals("X")){
buttons[3].setEnabled(false);
}
if (myButtons[0][4].getText().equals("O") || myButtons[0][4].getText().equals("X")){
buttons[4].setEnabled(false);
}
if (myButtons[0][5].getText().equals("O") || myButtons[0][5].getText().equals("X")){
buttons[5].setEnabled(false);
}
if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X")){
buttons[6].setEnabled(false);
if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X")){
buttons[6].setEnabled(false);
if (checkHorizontalWin(letter)
|| checkVerticalWin(letter)
|| checkDiagonalToTheLeftWin(letter)
|| checkDiagonalToTheRightWin(letter)
) {
win = true;
if (win == true) {
JOptionPane.showMessageDialog(null, letter + " has won!");
System.exit(0);
}
}
}
if(win == true){
JOptionPane.showMessageDialog(null, letter + " has won!");
System.exit(0);
} else if(count == 42 && win == false){
JOptionPane.showMessageDialog(null, "tie game");
System.exit(0);
}
}
}
public static void main(String[] args){
new Connect();
}
}

Identation helps.
if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X"))
{
buttons[6].setEnabled(false);
// Missing brace on previous if
// checkXWin methods only invoked inside the above if-statement.
if (checkHorizontalWin(letter)
|| checkVerticalWin(letter)
|| checkDiagonalToTheLeftWin(letter)
|| checkDiagonalToTheRightWin(letter)
) {
win = true;
if (win == true) {
JOptionPane.showMessageDialog(null, letter + " has won!");
ystem.exit(0);
}
}
}
You haven't closed a brace in one of your if statements properly in the actionPerformed method. As a result, your program will only check for a win once the last column is full.
It also seems the condition if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X") is repeated twice. That wouldn't be the cause of your issue but I think you might want to remove one of those statements.

Your brackets on your if statements are incorrectly placed.
if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X")){
buttons[6].setEnabled(false);
if (myButtons[0][6].getText().equals("O") || myButtons[0][6].getText().equals("X")){
buttons[6].setEnabled(false);
On both of theses if statements you have opening brackets but the closing brackets do not come until the end of the actionPerformed method.
This means the code to check for a winner does not get executed unless both of these conditions resulted in true, which is not what you want and I'm pretty sure is impossible...