(Java)

• Create a new Java project called TicTacToe2d and copy and Paste the below starter code into a file named TicTacToe2d.java

• For this activity, we will create a Tic-Tac-Toe board stored in a two-dimensional array

• Your job is to fill in the missing lines of code where indicated.

• When your program is running properly (see sample output below), submit it to Canvas.

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Starter Code:

/** * @author * CIS 36b * Activity 5.1 */ import java.util.Random; import java.util.Scanner; public class TicTacToe2d { /** * Initializes the board by assigning all array elements the value of '-' * @param board the array representing the tic-tac-toe board */ public static void initializeBoard(String board[][]) { //Fill in missing method body here } /** * Prints the board to the console in the form of a grid, * including column and row numbers * @param board the array representing the tic-tac-toe board */ public static void printBoard(String board[][]) { System.out.print(" Tic-Tac-Toe: "); for (int i = 1; i <= 3; i++) { System.out.print(" " + i); } System.out.println(); for (int i = 0; i < board.length; i++) { System.out.print((i + 1) + " "); //fill in for loop here System.out.println(); } } /** * Determines whether a particular position * on the board has already been taken. * @param board the array representing the game board * @param row the row to check * @param col the column to check * @return whether that position has already been taken */ public static boolean alreadyTaken(String board[][], int row, int col) { return (!board[row - 1][col - 1].equals("-")); } /** * Places an X or O into the correct position on the board. * Called when either the player or computer makes its move. * @param board the array representing the tic-tac-toe board * @param row the row in the array at which to place the X or O * @param col the column in the array at which to place the X or O * @param character either X or O */ public static void makePlacement(String board[][], int row, int col, String character) { //fill in missing line here } /** * Gives a random position on the board * Used for generating moves by the computer * @return a random row or column */ public static int randomPosition() { final int SIZE = 3; //3 X 3 array Random r = new Random(System.currentTimeMillis()); return r.nextInt(SIZE) + 1; } /** * Determines whether three Strings are all Xs or all Os * Used as a helper method to the gameOver method * @param a the first String to compare, either X, O, or - * @param b the second String to compare, either X, O, or - * @param c the third String to compare, either X, O or - * @return whether the Strings are all Xs or all Os */ public static boolean threeInRow(String a, String b, String c) { if (a.equals(b) && b.equals(c) && ! a.equals("-")) { return true; } return false; } /** * Determines whether the game is over * due to one player winning, using * a series of if statements. * Calls the threeInRow method for each * possible row on the board. * @param board the tic-tac-toe game board * @return whether the game is over */ public static boolean gameOverWinner(String board[][]) { boolean winner = false; //Check if winning across if (threeInRow(board[0][0], board[0][1], board[0][2])) { winner = true; } else if (threeInRow(board[1][0], board[1][1], board[1][2])) { winner = true; } else if (threeInRow(board[2][0], board[2][1], board[2][2])) { winner = true; //Fill in the missing 3 else if statements for winning going down //Check if winning diagonally } else if(threeInRow(board[0][0], board[1][1], board[2][2])) { winner = true; } else if(threeInRow(board[0][2], board[1][1], board[2][0])) { winner = true; } else { winner = false; } return winner; } /** * Determines whether the game is over * due to a draw. * Compares numMoves to the length. * @param board the tic-tac-toe game board * @return whether the game is over */ public static boolean gameOverDraw(String board[][]) { for (int i = 0; i < board.length; i++) { for (int j = 0; j < board[i].length; j++) { if (board[i][j].equals("-")) { return false; } } } return true; } public static void main(String[] args) { String board[][] = new String[3][3]; String player = " "; String computer = "X"; int row; int col; int numMoves = 0; System.out.println("Welcome to Tic-Tac-Toe!"); Scanner input = new Scanner(System.in); System.out.print(" Would you like to play as X or O: "); player = input.next().toUpperCase(); if (player.equals("X")) { computer = "O"; } initializeBoard(board); printBoard(board); while(!gameOverWinner(board) && !gameOverDraw(board)) { System.out.print(" Please enter your move: Row: "); row = input.nextInt(); System.out.print("Column: "); col = input.nextInt(); while (alreadyTaken(board, row, col)) { System.out.print(" That spot is already taken!" + " Please enter your move: Row:"); row = input.nextInt(); System.out.print("Column: "); col = input.nextInt(); } makePlacement(board, row, col, player); numMoves++; printBoard(board); if(gameOverWinner(board) || gameOverDraw(board)) { break; } row = randomPosition(); col = randomPosition(); while (alreadyTaken(board, row, col)) { row = randomPosition(); col = randomPosition(); } makePlacement(board, row, col, computer); numMoves++; System.out.println(" Counter move!"); printBoard(board); } if(gameOverWinner(board)) { if (numMoves % 2 == 0) { System.out.println(" " + computer + " wins!"); } else { System.out.println(" " + player + " wins!"); } } else { System.out.println(" It's a tie!"); } System.out.println(" ***Game Over***"); } } Sample Output:

Welcome to Tic-Tac-Toe! Would you like to play as X or O: X Tic-Tac-Toe: 1 2 3 1 - - - 2 - - - 3 - - - Please enter your move: Row: 2 Column: 2 Tic-Tac-Toe: 1 2 3 1 - - - 2 - X - 3 - - - Counter move! Tic-Tac-Toe: 1 2 3 1 - - - 2 - X - 3 - - O Please enter your move: Row: 3 Column: 1 Tic-Tac-Toe: 1 2 3 1 - - - 2 - X - 3 X - O Counter move! Tic-Tac-Toe: 1 2 3 1 O - - 2 - X - 3 X - O Please enter your move: Row: 1 Column: 3 Tic-Tac-Toe: 1 2 3 1 O - X 2 - X - 3 X - O X wins! ***Game Over***