CODE
import java.util.Scanner;
public class TicTacToeBasic {
// Name-constants to represent the seeds and cell contents
public static final int EMPTY = 0;
public static final int CROSS = 1;
public static final int NOUGHT = 2;
// Name-constants to represent the various states of the game
public static final int PLAYING = 0;
public static final int DRAW = 1;
public static final int CROSS_WON = 2;
public static final int NOUGHT_WON = 3;
// The game board and the game status
public static final int ROWS = 3, COLS = 3; // number of rows and columns
public static int[][] board = new int[ROWS][COLS]; // game board in 2D array
// containing (EMPTY, CROSS, NOUGHT)
public static int currentState; // the current state of the game
// (PLAYING, DRAW, CROSS_WON, NOUGHT_WON)
public static int currentPlayer; // the current player (CROSS or NOUGHT)
public static int currntRow, currentCol; // current seed's row and column
public static Scanner in = new Scanner(System.in); // the input Scanner
/** The entry main method (the program starts here)
* @param args */
public static void main(String[] args) {
// Initialize the game-board and current status
initGame();
// Play the game once
do {
playerMove(currentPlayer); // update currentRow and currentCol
updateGame(currentPlayer, currntRow, currentCol); // update currentState
printBoard();
// Print message if game-over
if (currentState == CROSS_WON) {
System.out.println("'X' won! Bye!");
} else if (currentState == NOUGHT_WON) {
System.out.println("'O' won! Bye!");
} else if (currentState == DRAW) {
System.out.println("It's a Draw! Bye!");
}
// Switch player
currentPlayer = (currentPlayer == CROSS) ? NOUGHT : CROSS;
} while (currentState == PLAYING); // repeat if not game-over
}
/** Initialize the game-board contents and the current states */
public static void initGame() {
for (int row = 0; row < ROWS; ++row) {
for (int col = 0; col < COLS; ++col) {
board[row][col] = EMPTY; // all cells empty
}
}
currentState = PLAYING; // ready to play
currentPlayer = CROSS; // cross plays first
}
/** Player with the "theSeed" makes one move, with input validation.
Update global variables "currentRow" and "currentCol".
* @param theSeed */
public static void playerMove(int theSeed) {
boolean validInput = false; // for input validation
do {
if (theSeed == CROSS) {
System.out.print("Player 'X', enter your move (row[1-3] column[1-3]): ");
} else {
System.out.print("Player 'O', enter your move (row[1-3] column[1-3]): ");
}
int row = in.nextInt() - 1; // array index starts at 0 instead of 1
int col = in.nextInt() - 1;
if (row >= 0 && row < ROWS && col >= 0 && col < COLS && board[row][col] == EMPTY) {
currntRow = row;
currentCol = col;
board[currntRow][currentCol] = theSeed; // update game-board content
validInput = true; // input okay, exit loop
} else {
System.out.println("This move at (" + (row + 1) + "," + (col + 1)
+ ") is not valid. Try again...");
}
} while (!validInput); // repeat until input is valid
}
/** Update the "currentState" after the player with "theSeed" has placed on
(currentRow, currentCol).
* @param theSeed
* @param currentRow
* @param currentCol */
public static void updateGame(int theSeed, int currentRow, int currentCol) {
if (hasWon(theSeed, currentRow, currentCol)) {
// check if winning move
currentState = (theSeed == CROSS) ? CROSS_WON : NOUGHT_WON;
}
else if (isDraw()) {
// check for draw
currentState = DRAW;
}
// Otherwise, no change to currentState (still PLAYING).
}
/** Return true if it is a draw (no more empty cell)
* @return */
public static boolean isDraw() {
for (int row = 0; row < ROWS; ++row) {
for (int col = 0; col < COLS; ++col) {
if (board[row][col] == EMPTY) {
return false; // an empty cell found, not draw, exit
}
}
}
return true; // no empty cell, it's a draw
}
/** Return true if the player with "theSeed" has won after placing at
(currentRow, currentCol)
* @param theSeed
* @param currentRow
* @param currentCol
* @return */
public static boolean hasWon(int theSeed, int currentRow, int currentCol) {
return (board[currentRow][0] == theSeed // 3-in-the-row
&& board[currentRow][1] == theSeed
&& board[currentRow][2] == theSeed
|| board[0][currentCol] == theSeed // 3-in-the-column
&& board[1][currentCol] == theSeed
&& board[2][currentCol] == theSeed
|| currentRow == currentCol // 3-in-the-diagonal
&& board[0][0] == theSeed
&& board[1][1] == theSeed
&& board[2][2] == theSeed
|| currentRow + currentCol == 2 // 3-in-the-opposite-diagonal
&& board[0][2] == theSeed
&& board[1][1] == theSeed
&& board[2][0] == theSeed);
}
/** Print the game board */
public static void printBoard() {
for (int row = 0; row < ROWS; ++row) {
for (int col = 0; col < COLS; ++col) {
printCell(board[row][col]); // print each of the cells
if (col != COLS - 1) {
System.out.print("|"); // print vertical partition
}
}
System.out.println();
if (row != ROWS - 1) {
System.out.println("-----------"); // print horizontal partition
}
}
System.out.println();
}
/** Print a cell with the specified "content"
* @param content */
public static void printCell(int content) {
switch (content) {
case EMPTY: System.out.print(" "); break;
case NOUGHT: System.out.print(" O "); break;
case CROSS: System.out.print(" X "); break;
}
}
}
OUTPUT
