Help with this method

[Douglas Henderson]

Hi, I am in need of help with this tic tac toe game. I have been working on it longer than I care to admit. I am trying to get it to compile correctly. I am working on the winorTie method and been having trouble figure out what code to insert. I understand that I need to write code that goes through the game board row by row and counts how many X's or O's have been marked. Yet every time I've inserted code it doesn't compile correctly. Right now I have the foundation for the if statement but unsure about the code.

 

Whenever I compile I get the below in the output section.

 

| | | |

------

| | | |
------

| | | |
------


-0's turn-

 

 

When compiled correctly it is supposed to look like this in the output section.

 

||||
-------
||||
-------
||||
-------
--O’s turn--
|O| | |
-------
||||
-------
||||
-------
--X’s turn--
|O|X| |
------- |||| ------- |||| -------

--O’s turn--
|O|X| |
-------
| |O| |
-------
||||
-------
--X’s turn--
|O|X| |
-------
| |O| |
-------
|X| | |
______
—O’s turn—
|O|X| |
-------
| |O| |
-------
|X| |O|
O wins!

 

 

 

Here is my current code..

/* * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package tictactoegame;


/**
 *
 * @author Doug Henderson
 */
public class tictactoegame {
    
    static int [] [] gameboard;
    static final int EMPTY = 0;
    static final int NOUGHT = -1;
    static final int CROSS = 1;
    
    static void set (int val, int row)
            throws IllegalArgumentException {
        int col = 0;
        if (gameboard[row] [col]  == EMPTY)
                gameboard[row] [col] = val;
        else throw new
            IllegalArgumentException("Player already there!");
    }
    
    static void displayBoard () {
        for (int[] gameboard1 : gameboard) {
            System.out.print("|");
            for (int c = 0; c < gameboard1.length; c++) {
                switch (gameboard1[c]) {
                    case NOUGHT:
                        System.out.print("0");
                        break;
                    case CROSS:
                        System.out.print("X");
                        break;
                    default:           //Empty
                        System.out.print(" ");
                }
                System.out.print("|");
            }
            System.out.println("\n------\n");
        }
    }
    static void createBoard(int rows, int cols) {
        gameboard = new int [rows] [cols];
    }
    
    static int winOrTie() {
    if (); 
           return ;
    else if ();
           return ;
    else if ();{    
           return ;
    else {
           return ;
                               
    }
           
  
    /**
     * @param args the command line arguments
     */    /**
     * @param args the command line arguments
     */
     
     public static void main(String[] args)  {
        createBoard(3,3);
        int turn = 0;
        int playerVal;
        int outcome;
        java.util.Scanner scan = new
            java.util.Scanner(System.in);
        do {
            displayBoard();
            playerVal = (turn % 2 == 0)? NOUGHT : CROSS;
            if (playerVal == NOUGHT) {
                System.out.println ("\n-0's turn-");
            } else {
                System.out.println("\n-X's turn-");
                }
            System.out.print("Enter row and Column:");
            try {
                set(playerVal, scan.nextInt());
            } catch (IllegalArgumentException ex)
            {System.err.println(ex);}
            turn ++;
            outcome = winOrTie();
        } while ( outcome == -2 );
        displayBoard();
        switch (outcome) {
            case NOUGHT:
                System.out.println("0 wins!");
                break;
            case CROSS:
                System.out.println("X wins!");
                break;
            case 0:
                System.out.println("Tie.");
                break;
            }
     }
     
}
 

Edited February 24, 2017 by Douglas Henderson

[justsomeguy]

The skeleton you have for the if structure isn't correct, you don't have enough brackets and you have too many semicolons. Look at the main method to see how to format an if/else structure.

[davej]

This code is almost too horrible to fix. Are you teaching yourself Java?

 

Do you really want a variable-sized board? That requires a fair amount of additional complexity.

[Ingolme]

I would say that a variable size board is good for learning. Regardless of the board size you have to go through rows, columns and two diagonals.

[davej]

Main should be simple and provide an outline of what you are doing. In my version of your program it looks like this...

public static void main(String[] args)  {

        gameboard = new int[SIZE][SIZE]; // board must be square
        int turn = 0;
        int outcome;
        displayBoard();
         
        do {
            turn = promptUser(turn);
            displayBoard();
            outcome = winOrTie();
            
        } while ( outcome == -2 );
        
        displayResults(outcome);
        
    }// end of main

[Douglas Henderson]

This is a small assignment I have been given. They have given me most of the code and I have to figure out the rest. My winorTie method is what I have to figure out. So yes I am pretty much teaching myself.

Modified it a bit adding brackets. Do I still have too many semicolons? I am trying to figure out what code to put in though. It is a work in progress.

Part of the directions...

The variable gameboard is a two-dimensional int array. Think of it as a table with rows and columns, and cells can be empty (0) or contain a nought (–1) or cross (1). The constants EMPTY, NOUGHT, and CROSS will simplify your code.

Define the winOrTie method. Check first for a win with rows and columns and then diagonally. Finally, check to see if there are any empty cells without a cross or nought.

static int winOrTie() {
   if ( ( ) ) {
      return CROSS;
} else if ( ( ) ) {
      return NOUGHT;
} else if ( ( ) ) {
     return
} else {
     return
}
 
}

Edited February 25, 2017 by Douglas Henderson

[Douglas Henderson]

The skeleton you have for the if structure isn't correct, you don't have enough brackets and you have too many semicolons. Look at the main method to see how to format an if/else structure.

 

 

Thank you, so the if/else structure in the below main method is the way to go?

displayBoard();
            playerVal = (turn % 2 == 0)? NOUGHT : CROSS;
            if (playerVal == NOUGHT) {
                System.out.println ("\n-0's turn-");
            } else {
                System.out.println("\n-X's turn-");
                }
            System.out.print("Enter row and Column:");
            try {
                set(playerVal, scan.nextInt());
            } catch (IllegalArgumentException ex)
            {System.err.println(ex);}
            turn ++;
            outcome = winOrTie();
        } while ( outcome == -2 );
        displayBoard();

[davej]

 

This is a small assignment I have been given. They have given me most of the code and I have to figure out the rest.

 

 

Given by who? This is terrible code. Don't learn to code like this. There are many books and tutorials available.

 

Begin with a main() something like this...

public static void main(String[] args)  {

        gameboard = new int[SIZE][SIZE]; // board must be square
        int outcome;
         
        do {
            displayBoard();
            promptUser();
            outcome = winOrTie();
            
        } while ( outcome == INCOMPLETE );
        
        displayResults(outcome);
        
    }// end of main

[davej]

static int winOrTie() {
   if ( ( ) ) {
      return CROSS;
} else if ( ( ) ) {
      return NOUGHT;
} else if ( ( ) ) {
     return
} else {
     return
}
 
}

This approach can only be used if the board is a fixed size. If you know it is always a 3 x 3 board then it is easy to formulate an if structure. Something simple like this could work...

if(gameboard[0][0] + gameboard[0][1] + gameboard[0][2] == 3*NOUGHT){return NOUGHT;}
if(gameboard[1][0] + gameboard[1][1] + gameboard[1][2] == 3*NOUGHT){return NOUGHT;}
if(gameboard[2][0] + gameboard[2][1] + gameboard[2][2] == 3*NOUGHT){return NOUGHT;}

if(gameboard[0][0] + gameboard[1][0] + gameboard[2][0] == 3*NOUGHT){return NOUGHT;}
if(gameboard[0][1] + gameboard[1][1] + gameboard[2][1] == 3*NOUGHT){return NOUGHT;}
if(gameboard[0][2] + gameboard[1][2] + gameboard[2][2] == 3*NOUGHT){return NOUGHT;}

if(gameboard[0][0] + gameboard[1][1] + gameboard[2][2] == 3*NOUGHT){return NOUGHT;}
if(gameboard[0][2] + gameboard[1][1] + gameboard[2][0] == 3*NOUGHT){return NOUGHT;}

if(gameboard[0][0] + gameboard[0][1] + gameboard[0][2] == 3*CROSS){return CROSS;}
if(gameboard[1][0] + gameboard[1][1] + gameboard[1][2] == 3*CROSS){return CROSS;}
if(gameboard[2][0] + gameboard[2][1] + gameboard[2][2] == 3*CROSS){return CROSS;}

if(gameboard[0][0] + gameboard[1][0] + gameboard[2][0] == 3*CROSS){return CROSS;}
if(gameboard[0][1] + gameboard[1][1] + gameboard[2][1] == 3*CROSS){return CROSS;}
if(gameboard[0][2] + gameboard[1][2] + gameboard[2][2] == 3*CROSS){return CROSS;}

if(gameboard[0][0] + gameboard[1][1] + gameboard[2][2] == 3*CROSS){return CROSS;}
if(gameboard[0][2] + gameboard[1][1] + gameboard[2][0] == 3*CROSS){return CROSS;}

if(turn < 9){
    return INCOMPLETE;
}else{
    return TIE;
}

[Douglas Henderson]

 

 

Given by who? This is terrible code. Don't learn to code like this. There are many books and tutorials available.

 

Begin with a main() something like this...

public static void main(String[] args)  {

        gameboard = new int[SIZE][SIZE]; // board must be square
        int outcome;
         
        do {
            displayBoard();
            promptUser();
            outcome = winOrTie();
            
        } while ( outcome == INCOMPLETE );
        
        displayResults(outcome);
        
    }// end of main

 

 

It has been given by my school.

[Douglas Henderson]

Quick question, where did you get the number 9 from and 'incomplete'? Also should I also put in 'EMPTY' in with the code...example..

if(gameboard[0][0] + gameboard[0][1] + gameboard[0][2] == 3*EMPTY){return EMPTY;}
if(gameboard[1][0] + gameboard[1][1] + gameboard[1][2] == 3*EMPTY){return EMPTY;}
if(gameboard[2][0] + gameboard[2][1] + gameboard[2][2] == 3*EMPTY){return EMPTY;}

Thank you

[Ingolme]

There can be no more than 9 turns on the board, if nobody has won and less than 9 turns have passed then the game is still in progress.

INCOMPLETE would be a constant meaning the same thing as -2 did in your previous code.

 

There's no need to test for empty, since having three empty slots in a row doesn't end the game.

[davej]

There are almost always several different ways to approach any programming problem, and that is true here, but you first need to logically understand what you are trying to accomplish, and usually you also want to think of a few simple "test cases" to help you verify your thinking and your code.

 

Your above question makes me wonder if you logically understand what the code needs to do? How would you write code to detect that at least one square on the board is empty? You can use pencil and paper to help you reason through the problem. My code sample uses a global "turn" variable but you could also test the values on the gameboard. How would you do that?

 

Also what are you using to write this code? Eclipse? Netbeans? Whatever it is you should learn to use the debugger so that you can single-step through your code.

 

I would also suggest that you sign up here...

 

https://www.hackerrank.com/

 

...and try working the introductory Java practice problems.

[Douglas Henderson]

Thank you, I am using Netbeans.

[davej]

Here is a demonstration of the Netbeans debugger. See...

 

https://www.youtube.com/watch?v=2Z9B8wYhKWw