Tic Tac Toe

[Madord]

Hey All,

So I'm running thru Jumping into C++ and I have just finished my Tic Tac Toe game and just wanted to get some input on the final Product. Its not perfect but it plays a game, it can check for a Valid move thats Played between 0 and 8 but goes into an endless loop if a Char is entered.

So anyway. any hints or Tips would be great.

//Tic Tac Toe Program. 2 Players Play until the computer determines if 1 player has won#include <iostream>




using namespace std;


/*Used to draw the Game board on the Screen*/
void cDrawBoard(char cBoard[])
{
    cout << endl << endl << endl;
    cout << " " << cBoard[0] << " | " << cBoard[1] << " | " << cBoard[2] << endl;
    cout << "------------" << endl;
    cout << " " << cBoard[3] << " | " << cBoard[4] << " | " << cBoard[5] << endl;
    cout << "------------" << endl;
    cout << " " << cBoard[6] << " | " << cBoard[7] << " | " << cBoard[8] << endl;
    cout << endl << endl << endl;
}


int nCheckifXWins(char cBoard[], int& nPlayerXWins)
{
    nPlayerXWins = 0;
    if ((cBoard[0] == 'X' && cBoard[1] == 'X' && cBoard[2] == 'X') ||
            (cBoard[0] == 'X' && cBoard[3] == 'X' && cBoard[6] == 'X') ||
            (cBoard[0] == 'X' && cBoard[4] == 'X' && cBoard[8] == 'X') ||
            (cBoard[1] == 'X' && cBoard[4] == 'X' && cBoard[7] == 'X') ||
            (cBoard[2] == 'X' && cBoard[5] == 'X' && cBoard[8] == 'X') ||
            (cBoard[2] == 'X' && cBoard[4] == 'X' && cBoard[6] == 'X') ||
            (cBoard[3] == 'X' && cBoard[4] == 'X' && cBoard[5] == 'X') ||
            (cBoard[6] == 'X' && cBoard[7] == 'X' && cBoard[8] == 'X'))
    {
        //cout << "X Wins";
        nPlayerXWins = 1;
        return nPlayerXWins;
    }
    else
    {
        return nPlayerXWins;
    }
}


int nCheckifOWins(char cBoard[], int& nPlayerOWins)
{
    nPlayerOWins = 0;
    if ((cBoard[0] == 'O' && cBoard[1] == 'O' && cBoard[2] == 'O') ||
            (cBoard[0] == 'O' && cBoard[3] == 'O' && cBoard[6] == 'O') ||
            (cBoard[0] == 'O' && cBoard[4] == 'O' && cBoard[8] == 'O') ||
            (cBoard[1] == 'O' && cBoard[4] == 'O' && cBoard[7] == 'O') ||
            (cBoard[2] == 'O' && cBoard[5] == 'O' && cBoard[8] == 'O') ||
            (cBoard[2] == 'O' && cBoard[4] == 'O' && cBoard[6] == 'O') ||
            (cBoard[3] == 'O' && cBoard[4] == 'O' && cBoard[5] == 'O') ||
            (cBoard[6] == 'O' && cBoard[7] == 'O' && cBoard[8] == 'O'))
    {
        //cout << "O Wins";
        nPlayerOWins = 1;
        return nPlayerOWins;
    }
    else
    {
        return nPlayerOWins;
    }


}


int main()
{
    int nPlayerXWins = 0;
    int nPlayerOWins = 0;
    bool nPlayer = true; //true = X
    int nMove;
    char cBoard[9] = {'0','1','2','3','4','5','6','7','8'}; // Sets the Board to have 0 - 8 in each Square.
    //cDrawBoard(cBoard); //Draws the Initial Board on the screen


    for (int nGame = 0; nGame < 9; nGame++) // Sets the game to run for 9 moves
    {
        if (nPlayer == true) //when nplayer == true - X's turn
            {
            for (int nValidMove = 0; nValidMove != 1;) //Variable if a valid move or asks for a new move.
            {
                cDrawBoard(cBoard); //Draws the Board
                cout << "Player X - Please Enter your move: ";
                cin >> nMove;
                if ((cBoard[nMove] != 'X' || cBoard[nMove] != 'O') &&
                    (nMove >= 0 && nMove <= 8)) //Checks the move is Valid?
                {
                    cBoard[nMove] = 'X'; //Places an X at the selected Square
                    nValidMove = 1;
                    nCheckifXWins(cBoard, nPlayerXWins); //Checks to see if wins and returns a value of 1 to end the game
                    nPlayer = false; // Switches the player
                    if (nPlayerXWins > 0)   //ends the game
                    {
                        cout << endl << "Player X has Won!";
                        nGame = 10;
                        break;
                    }
                }
                else
                {
                    cout << "Please enter a Valid Move.";
                }
            }
            }
            else if (nPlayer == false)
            {
                for (int nValidMove = 0; nValidMove != 1;)
                {
                    cDrawBoard(cBoard);
                    cout << "Player O - Please Enter your move: ";
                    cin >> nMove;
                    if ((cBoard[nMove] != 'X' || cBoard[nMove] != 'O') &&
                        (nMove >= 0 && nMove <= 8))
                    {
                        cBoard[nMove] = 'O';
                        nValidMove = 1;
                        nCheckifOWins(cBoard, nPlayerOWins);
                        nPlayer = true;
                        if (nPlayerOWins > 0)
                        {
                            cout << endl <<"Player O has won!";
                            nGame = 10;
                            break;
                        }
                    }
                    else
                    {
                        cout << "Please enter a Valid Move.";
                    }
                }




            }
    }
}

[GReaper]

To check whether an input error has happened, you can do:

if (!(cin >> nMode))
    // Error, clean the input stream, clear the fail bit and try again

or:

cin >> nMode;
if (cin.fail())
    // Same as the above

EDIT: Remember to clear the state before trying to receive any new input, by "cin.clear()"

[iMalc]

If I were to declare an array like so:

static const int[][3] = {{0,1,2},{3,4,5},{6,7,8},{0,3,6},{1,4,7},{2,5,8},{1,5,9},{2,4,6}};

Can you see how a loop with a much shorter if-statement can be used to check for all possible wins?
It's called a lookup table, and they really rock for this kind of thing
You should also be able to combine the methods that check for O and X wins, by passing in an 'O' or an 'X' as a parameter.

You don't need to both return a value and use an out-parameter. Just use the return value and make sure you use the result where you call the function.