Tic Tac Toe help

[FoxTek]

I need to make this program 'smarter' instead of it just making random moves. Any and all help would be appreciated.

package tictactoe;

import java.util.Random;
import java.util.Scanner;

public class TicTacToe {
	private char[] cells = new char[9];
	public static char CELL_EMPTY = ' ';
	public static char CELL_CIRCLE = 'O';
	public static char CELL_CROSS = 'X';

	public TicTacToe() {
		for (int i = 0; i < cells.length; i++) {
			cells[i] = CELL_EMPTY;
		}
	}
	
	private void drawBoard() {
		System.out.println(cells[0] + " | " + cells[1] + " | " + cells[2]);
		System.out.println("- - - - -");
		System.out.println(cells[3] + " | " + cells[4] + " | " + cells[5]);
		System.out.println("- - - - -");
		System.out.println(cells[6] + " | " + cells[7] + " | " + cells[8]);
	}

	private boolean isWinner(char symbol) {
		boolean answer = false;
		if (checkRows(symbol) || checkColumns(symbol) || checkDiagnals(symbol)) {
			answer = true;
		} else {
			answer = false;
		}
		return answer;
	}
	
	public void computerMove() {
		System.out.println("======================================");
		System.out.println("Thinking . . .");
		try {
			Thread.sleep(2000);
		}
		catch (InterruptedException ie) {
		}
		System.out.println("Making move . . .");
		try {
			Thread.sleep(2000);
		}
		catch (InterruptedException ie) {
		}
		int emptyCellCount = 0;
		for (int i = 0; i < cells.length; i++) {
			if (cells[i] == CELL_EMPTY) {
				emptyCellCount++;
			}
		}
		
		int[] emptyCellIndexes = new int[emptyCellCount];
		emptyCellCount = 0;
		for (int i = 0; i < cells.length; i++) {
			if (cells[i] == CELL_EMPTY) {
				emptyCellIndexes[emptyCellCount] = i;
				emptyCellCount++;
			}
		}
		
		Random r = new Random();
		int randomNumber = r.nextInt(emptyCellCount);

		cells[emptyCellIndexes[randomNumber]] = CELL_CIRCLE;
		
		drawBoard();
		
		if (isWinner(CELL_CROSS)) {
			System.out.println("Congratulations! You won.");
		} else if (isWinner(CELL_CIRCLE)) {
			System.out.println("Sorry! You lost.");
		} else if (isFull()) {
			System.out.println("It's a tie!");
		} else {
			humanMove();
		}		
	}
	
	public void humanMove() {
		System.out.println("======================================");
		drawBoard();
		Scanner input = new Scanner(System.in);
		int rowNumber = 0, colNumber = 0, index = 0;
		try {
			Thread.sleep(1000);
		}
		catch (InterruptedException ie) {
		}
		System.out.println("You are 'X'. It's your turn. ");
		System.out.println("Tell me which cell you would like to occupy.");
		System.out.println("Which row [1 - 3]? ");
		rowNumber = input.nextInt();
		System.out.println("Which column [1 - 3]? ");
		colNumber = input.nextInt();
		index = (rowNumber - 1) * 3 + (colNumber - 1);
		while (!isInputValid(index)) {
			System.out.println("Invalid move! Tell me which cell you would like to occupy.");
			System.out.println("Which row [1 - 3]? ");
			rowNumber = input.nextInt();
			System.out.println("Which column [1 - 3]? ");
			colNumber = input.nextInt();
			index = (rowNumber - 1) * 3 + (colNumber - 1);
		}
		cells[index] = CELL_CROSS;
drawBoard();
		if (isWinner(CELL_CROSS)) {
			System.out.println("Congratulations! You won.");
			drawBoard();
		} else if (isWinner(CELL_CIRCLE)) {
			System.out.println("Sorry! You lost.");
			drawBoard();
		} else if (isFull()) {
			System.out.println("It's a tie!");
			drawBoard();
		}
		else {
			computerMove();
		}
	}
	private boolean isFull() {
		boolean answer = true;
		for (int i = 0; i < cells.length; i++) {
			if (cells[i] == CELL_EMPTY) {
				answer = false;
				break;
			}
		}
		return answer;
	}
	
	private boolean isInputValid(int index) {
		boolean answer = false;
		if (cells[index] == CELL_CIRCLE || cells[index] == CELL_CROSS) {
			answer = false;
		} else {
			answer = true;
		}
		return answer;
	}

	private boolean checkRows(char symbol) {
		boolean answer = false;
		if (cells[0] == symbol && cells[1] == symbol && cells[2] == symbol){
			answer = true;
		} else if (cells[3] == symbol && cells[4] == symbol && cells[5] == symbol) {
			answer = true;
		} else if (cells[6] == symbol && cells[7] == symbol && cells[8] == symbol) {
			answer = true;
		} else {
			answer = false;
		}
		return answer;
	}
	
	private boolean checkColumns(char symbol) {
		boolean answer = false;
		if (cells[0] == symbol && cells[3] == symbol && cells[6] == symbol){
			answer = true;
		} else if (cells[1] == symbol && cells[4] == symbol && cells[7] == symbol) {
			answer = true;
		} else if (cells[2] == symbol && cells[5] == symbol && cells[8] == symbol) {
			answer = true;
		} else {
			answer = false;
		}
		return answer;
	}
	
	private boolean checkDiagnals(char symbol) {
		boolean answer = false;
		if (cells[0] == symbol && cells[4] == symbol && cells[8] == symbol) {
			answer = true;
		} else if (cells[2] == symbol && cells[4] == symbol && cells[6] == symbol) {
			answer = true;
		} else {
			answer = false;
		}
		return answer;
	}
}

 

[aznguy94]

make some sort of scoring system where the computer associates moving a certain position to a certain score, then it will move to the place with the highest score

basically the ai is thinking one move ahead


i remember doing a tic tac toe ai when i started learning c++, i may dig it up and see what i did


maybe score based on how many marks in a row it has? and how many marks in a row the opponent has?

 

[iskilli]

Woo i learned tic tac toe a while ago.. alot of uneeded methods. Good conventions

 

[Cody]

Construct a 2D array with all the possible win combination's for tic-tac-toe, Code your bot to choose a random index of that array and work towards it.

Example:

The method says, Ok choose wincombination #3, that one is bottom left, middle, and top right....

Ok, if bottom left and middle and top right are all empty, then choose a random one of those and place an X.


If all 3 are NOT empty, then choose another way to win.

This way your "AI" will always be trying to actually win the game.

 

[Govind]

OMG CODY HOLY CRAP ITS CODY CODY HOLY CRAP hi dude