TicTacToe AI Java

So I thought i’d come back after finding the old code I did for this and answer how I did it.

It’s probably still far from perfect but it’s very close.

I started with a very simple class of player which would get and set markers.

public class player {

    public String Marker;

    // set marker method

    public void setMarker(String marker){

        Marker = marker;

    }

    //get marker method 

    public String getMarker(){

        return Marker;

    }

}

I then added a set class which would set up and print the board after each move.

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



public class set {

    // setup variables default board size and board
    private int N = 3;
    public String[][] board = new String [N][N];

    public boolean hasWon (String [] [] board){
        //horizontal 
        for(int i = 0; i<3; i++){
            if(board[i][0].equals(board[i][1]) && board[i][1].equals(board[i][2])){
                return true;
            }
        }
        //vertical
        for(int i = 0; i<3; i++){
            if(board [0][i].equals(board[1][i]) && board[1][i].equals(board[2][i])){
                return true;
            }
        }
        //diagonal
        if(board[0][0].equals(board[1][1]) && board[1][1].equals(board[2][2]) || board[2][0].equals(board[1][1]) && board[1][1].equals(board[0][2]))
            return true;
        return false;
    }


    int x = 1;

    public void createBoard(){
        for(int i = 0; i < board.length; i++){
            for(int j = 0; j < board.length; j++){
                board[i][j] = "" + (x);
                x++;
            }
        }
    }

    public void printBoard(){

        for(int i = 0; i < board.length; i++){
            for(int j = 0; j < board.length; j++){
                System.out.print("[" + board[i][j] + "]" + " ");

            }
            System.out.println();
        }

    }

    public String[][] getBoard(){

        return board;

    }



}

The Computer class with AI.

class Computer extends player {

public Computer(){

}

int boardsize = 3;


public void takeTurn(String[][] board, Human human) {

    int vertical = 0;
    int horizontal = 0;
    int diagonal = 0;
    boolean mademove = false;

    // check if you can take a win horizontally
    for(int i = 0; i<3; i++){

        if(board[0][i].equals(board[1][i]) && board[0][i].equals(Marker)){

            if(board[2][i] != human.getMarker() && board[2][i] != Marker){
                board[2][i] = Marker;
                mademove = true;
                return;
            }

        }

    }

    for(int i = 0; i<3; i++){

        if(board[2][i].equals(board[1][i]) && board[2][i].equals(Marker)){

            if(board[0][i] != human.getMarker() && board[0][i] != Marker){
                board[0][i] = Marker;
                mademove = true;
                return;
            }

        }


    }



    // check if you can take a win horizontally
    for(int i = 0; i<3; i++){

        if(board[i][0].equals(board[i][1]) && board[i][0].equals(Marker)){

            if(board[i][2] != human.getMarker() && board[i][2] != Marker){
                board[i][2] = Marker;
                mademove = true;
                return;
            }

        }

    }

    for(int i = 0; i<3; i++){

        if(board[i][2].equals(board[i][1]) && board[i][2].equals(Marker)){

            if(board[i][0] != human.getMarker() && board[i][0] != Marker){
                board[i][0] = Marker;
                mademove = true;
                return;
            }

        }

    }


    // check if you can take a win diagonally bottom


    if(board[0][0].equals(board[1][1]) && board[0][0].equals(Marker)){

        if(board[2][2] != human.getMarker() && board[2][2] != Marker){
            board[2][2] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[2][2].equals(board[1][1]) && board[2][2].equals(Marker)){

        if(board[0][0] != human.getMarker() && board[0][0] != Marker){
            board[0][0] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[0][0].equals(board[1][1]) && board[0][0].equals(Marker)){

        if(board[2][2] != human.getMarker() && board[2][2] != Marker){
            board[2][2] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[0][2].equals(board[1][1]) && board[0][2].equals(Marker)){

        if(board[2][0] != human.getMarker() && board[2][0] != Marker){
            board[2][0] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[2][0].equals(board[1][1]) && board[2][0].equals(Marker)){

        if(board[0][2] != human.getMarker() && board[0][2] != Marker){
            board[0][2] = Marker;
            mademove = true;
            return;
        }
    }


    // BLOCKS!!!! //

    // check if you can block a win horizontally
    for(int i = 0; i<3; i++){

        if(board[0][i].equals(board[1][i]) && board[0][i].equals(human.getMarker())){
            if(board[2][i] != Marker && board[2][i] != human.getMarker()){
                board[2][i] = Marker;
                mademove = true;
                return;
            }

        }

    }

    for(int i = 0; i<3; i++){

        if(board[2][i].equals(board[1][i]) && board[0][i].equals(human.getMarker())){

            if(board[0][i] != Marker && board[0][i] != human.getMarker()){
                board[0][i] = Marker;
                mademove = true;
                return;
            }

        }


    }

    // check if you can block a win vertically


    for(int i = 0; i<3; i++){

        if(board[i][0].equals(board[i][1]) && board[i][0].equals(human.getMarker())){

            if(board[i][2] != Marker && board[i][2] != human.getMarker()){
                board[i][2] = Marker;
                mademove = true;
                return;
            }

        }

    }

    for(int i = 0; i<3; i++){

        if(board[i][2].equals(board[i][1]) && board[i][2].equals(human.getMarker())){

            if(board[i][0] != Marker && board[i][0] != human.getMarker()){
                board[i][0] = Marker;
                mademove = true;
                return;
            }

        }

    }

    for(int i = 0; i<3; i++){

        if(board[2][i].equals(board[1][i]) && board[2][i].equals(human.getMarker())){

            if(board[0][i] != Marker && board[0][i] != human.getMarker()){
                board[0][i] = Marker;
                mademove = true;
                return;
            }

        }

    }



    // check if you can block a win diagonally 


    if(board[0][0].equals(board[1][1]) && board[0][0].equals(human.getMarker())){

        if(board[2][2] != Marker && board[2][2] != human.getMarker()){
            board[2][2] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[2][2].equals(board[1][1]) && board[2][2].equals(human.getMarker())){

        if(board[0][0] != Marker && board[0][0] != human.getMarker()){
            board[0][0] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[0][0].equals(board[1][1]) && board[0][0].equals(human.getMarker())){
        if(board[2][2] != Marker && board[2][2] != human.getMarker()){
            board[2][2] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[0][2].equals(board[1][1]) && board[0][2].equals(human.getMarker())){

        if(board[2][0] != Marker && board[2][0] != human.getMarker()){
            board[2][0] = Marker;
            mademove = true;
            return;
        }
    }

    if(board[2][0].equals(board[1][1]) && board[2][0].equals(human.getMarker())){

        if(board[0][2] != Marker && board[0][2] != human.getMarker()){
            board[0][2] = Marker;
            mademove = true;
            return;
        }
    }




    // make random move if above rules dont apply
    int rand1 = 0;
    int rand2 = 0;

    while(!mademove){

        rand1 = (int) (Math.random() * 3);
        rand2 = (int) (Math.random() * 3);

        if(board[rand1][rand2] != "x" && board[rand1][rand2] != "o"){
            board[rand1][rand2] = Marker;
            mademove = true;        

        }

    }


}   

}

Human class

import java.util.Scanner;

class Human extends player {

public Human(){

}


public void takeTurn(String[][] board) {

    Scanner s = new Scanner(System.in);

    boolean turn = true;

    while(turn){
        System.out.println("please enter row");
        int row = s.nextInt();
        System.out.println("please enter col");
        int col = s.nextInt();
        System.out.print("you entered "+row+" "+col);
        System.out.println();
        if(board[row - 1][col - 1] != "x" && board[row - 1][col - 1] != "o"){
            board[row - 1][col - 1] = Marker;
            turn = false;
        } // closes if
        else {
            System.out.println("Already Marker here! please guess again!");
        }
    } // ends while
} // ends method

} // ends class

Finally the playing of the game.

    import java.util.Scanner;

public class play {



    public static void main(String[] args) {


        System.out.println("Welcome to Tickle Tackle Toe!!! :D");
        System.out.println();

        //creat markers
        String marker1 = "x";
        String marker2 = "o";
        boolean playAgain = true;

        Scanner s = new Scanner(System.in);



        //create player objects
        Human human = new Human();
        Computer computer = new Computer();

        while(playAgain){
            //run board setup
            set Setup = new set();

            Setup.createBoard();
            Setup.printBoard();

            System.out.println("please choose your marker");
            System.out.println("type 1 for 'x' or 2 for 'o'");

            //set markers
            if(s.nextInt() == 1){
                // create player objects
                human.setMarker("x");
                computer.setMarker("o");
            } 
            else
            {
                human.setMarker("o");
                computer.setMarker("x");

            }




            // determine who goes first
            int first = (int) (Math.random() * 2);





            boolean won = false;
            int turns = 0;

            if(first == 0){
                System.out.println("You gots the winz!");
                System.out.println();
                while(!won){
                    human.takeTurn(Setup.getBoard());
                    turns++;
                    Setup.printBoard();
                    if(Setup.hasWon(Setup.getBoard())){
                        won = true;
                        System.out.println("Congrats you won!");
                    }
                    if(turns == 9){
                        won = true;
                        System.out.println("Its a bore draw!");
                        break;
                    }
                    if(!won){
                        computer.takeTurn(Setup.getBoard(), human);
                        turns++;
                        System.out.println();
                        Setup.printBoard();
                        System.out.println();
                        if(Setup.hasWon(Setup.getBoard())){
                            won = true;
                            System.out.println("You just got pwned by an A.I with an incomplete rule set. FACEPALM.");
                        }
                        if(turns == 9){
                            won = true;
                            System.out.println("Its a bore draw!");
                            break;
                        }
                    }

                }  // close while 1
            }
            else {

                System.out.println("Computer goes first!");
                System.out.println();
                while(!won){
                    computer.takeTurn(Setup.getBoard(), human);
                    turns++;
                    Setup.printBoard();
                    if(Setup.hasWon(Setup.getBoard())){
                        won = true;
                        System.out.println("You just got pwned by an A.I with an incomplete rule set. FACEPALM.");
                    }
                    if(turns == 9){
                        won = true;
                        System.out.println("Its a draw!");
                        break;
                    }
                    if(!won){
                        human.takeTurn(Setup.getBoard());
                        turns++;
                        System.out.println();
                        Setup.printBoard();
                        System.out.println();
                        if(Setup.hasWon(Setup.getBoard())){
                            won = true;
                            System.out.println("You gots the winz!");
                        }
                        if(turns == 9){
                            won = true;
                            System.out.println("Its a draw!");
                            break;
                        }
                    }



                }  // close while 2

            }

            System.out.println("Would you like to play again? Type 1 for yes or 2 to quit");
            System.out.println();
            if(s.nextInt() == 2){
                playAgain = false;
            }

        }

    }
}

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