Basic Console Tic Tac Toe game

[jsladerman]

So I started learning C++ a few years ago and got a little bit past console programming but then I stopped and just recently started up again. I did some basic stuff like a calculator and fraction calculator and I want to start working on things a little bit more complicated. So I took a stab at writing a basic tic tac toe program. After working for about a day I finished and as far as I've tested it works except that it won't say who wins or loses, the game will just end. It's also a really inefficient code so I'm wondering if someone can give me some tips on it. Here it is:

#include <iostream>
#include <string>

using namespace std;

const int ROWsnum = 3;
const int COLsnum = 3;
int row;
int col;
int winner = 0;
bool gameover = false;
char board[COLsnum][ROWsnum] = { {' ', ' ', ' '}, {' ', ' ', ' '}, {' ', ' ', ' '} };
string playername1;
string playername2;

void printboard()
{
	cout << board[0][2] << " | " << board[1][2] << " | " << board[2][2] << endl;
	cout << "__________" << endl;
	cout << board[0][1] << " | " << board[1][1] << " | " << board[2][1] << endl;
	cout << "__________" << endl;
	cout << board[0][0] << " | " << board[1][0] << " | " << board[2][0] << endl;
}

void movex()
{
	cout << "Column:";
	cin >> col;
	cout << endl << "Row:";
	cin >> row;
	board[col][row] = 'X';
}

void moveo()
{
	cout << "Column:";
	cin >> col;
	cout << endl << "Row:";
	cin >> row;
	board[col][row] = 'O';
}

void checkwinner()
{
	if (gameover == false)
	{
		winner = -1;
	}
	else if (board[0][2] == board[1][2] == board[2][2])
	{
		if(board[0][2] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[0][1] == board[1][1] == board[2][1])
	{
		if(board[0][1] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[0][0] == board[1][0] == board[2][0])
	{
		if(board[0][0] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[0][0] == board[0][1] == board[0][2])
	{
		if(board[0][0] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[1][0] == board[1][1] == board[1][2])
	{
		if(board[1][0] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[2][0] == board[2][1] == board[2][2])
	{
		if(board[2][0] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[0][2] == board[1][1] == board[2][0])
	{
		if(board[0][2] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (board[0][0] == board[1][1] == board[2][2])
	{
		if(board[0][0] == 'X')
		{
			winner = 1;
		}
		else
		{
			winner = 2;
		}
	}
	else if (gameover == true)
	{
		winner = 5;
	}
	system("PAUSE");
}

void checkgameover()
{
	int otherc = 5;
	for(int c = 0; c <= 2; c++)
	{
		for(int r = 0; r <= 2; r++)
		{
			if(board[c][r] == ' ')
			{
				gameover = false;
				c = 5;
				r = 5;
				otherc = 10;
			}
		}
	}
	if(otherc == 5)
	{
		gameover == true;
	}
	else if(otherc == 10)
	{

	}
}

void main()
{
	cout << "Welcome to the game!" << endl << endl;
	cout << "Player 1, enter your name:";
	cin >> playername1;
	cout << "Hello " << playername1 << ", you are X." << endl;
	cout << "Player 2, enter your name:";
	cin >> playername2;
	cout << "Hello " << playername2 << ", you are O." << endl;
	system("PAUSE>nul");
	cout << "So " << playername1 << ", its you're turn." << endl;
	cout << "To move, enter the column you would like to choose and press return." << endl << "Then enter the row you would like to choose and press return." << endl;
	cout << "The bottom left is Col:0 and Row:0, the middle is Col:1 and Row:1, and the top right is Col:2 and Row:2" << endl;
	printboard();
	movex();
	printboard();
	cout << endl << "Now its " << playername2 << "'s turn." << endl;
	moveo();
	printboard();
	for(int i = winner; i <= 1; i++)
	{
		cout << endl << "X turn" << endl;
		movex();
		printboard();
		cout << endl << "O turn" << endl;
		moveo();
		printboard();
		checkgameover();
		checkwinner();
		if(winner == 5)
		{
			cout << "Stale mate. Nobody wins.";
			system("PAUSE>nul");
		}
		else if (winner == 1)
		{
			cout << "Congrats " << playername1 << "! X wins!" << endl;
			system("PAUSE>nul");
		}
		else if (winner == 2)
		{
		cout << "Congrats " << playername2 << "! O wins!" << endl;
		system("PAUSE>nul");
	}
}
}

[kevinkjt2000]

I went and dug up some old code that I wrote a while back for checking the winner on a tic-tac-toe board:

int TicTacToe::GetStatus(){ //returns 0 representing a tie, 1 representing a win by Player1, 2 representing a win by Player2, and 3 otherwise.
	for(int i=0; i<3; i++){
		if (board[i][0]==board[i][1] && board[i][1]==board[i][2]){ // 3 in a row check
			if (board[i][0]=='X') return 1;
			if (board[i][0]=='O') return 2;
		}
		if (board[0][i]==board[1][i] && board[1][i]==board[2][i]){ // 3 in a column check
			if (board[0][i]=='X') return 1;
			if (board[0][i]=='O') return 2;
		}
	}
	if ((board[0][0]==board[1][1] && board[1][1]==board[2][2]) || (board[0][2]==board[1][1] && board[1][1]==board[2][0])){
		if (board[1][1]=='X') return 1; // 3 in a diagonal check
		if (board[1][1]=='O') return 2;
	}
	bool tieTest = true;
	for (int i=0; i<3; i++) // checks for tie game
		for(int j=0; j<3; j++)
			if (board[i][j]==' ') tieTest = false;
	if (tieTest) return 0;
	return 3;
}

I hope this helps with you finding the winner or loser.

As far as what tips I may have to offer... I just have to say repeated code usually means you can write a new function from the repeated code.

[DesiredNote]

I would simplify the board by using '1' - '9' rather than having to input the column and row. You also shouldn't have global variables. If you need to get a variable to a function, then simply pass it to the function! They are bad practice and completely unnecessary. You could re-code it and get it finished in about 70 lines of code.

Here are two functions I wrote about two months ago. They aren't anything special, but it gets the job done.

bool checkWin(const char board[3][3], const char p1, const char p2) {
	for(int l = 0; l < 2; ++l) {
		const char cP = (l == 0?p1:p2); // currentPlayer
		for(int i = 0; i < 3; ++i) {
			for(int x = 0; x < 3; ++x) {
				if(board[i][0] == cP && board[i][x+1] == cP && board[i][x+2] == cP) // horizontal win
					return true;
				else if(board[i][x] == cP && board[i+1][x] == cP && board[i+2][x] == cP) // vertical win
					return true;
			}
		}
	}
	return false;
}

void newMove(char board[3][3], const char currentPlayer, const int newSpot) {
	int counter = 1;
	for(int i = 0; i < 3; ++i) {
		for(int x = 0; x < 3; ++x, ++counter) {
			if(counter == newSpot && (board[i][x] != 'X' && board[i][x] != 'O'))
				board[i][x] = currentPlayer;
		}
	}
}

I went and dug up some old code that I wrote a while back for checking the winner on a tic-tac-toe board:

Is there any reason why TicTacToe was a class?

[kevinkjt2000]

Yeah it was for a class. Pun fully intended.

[jsladerman]

Ok thanks for the help. Is there anything you guys recommend for going beyond console programs? They're getting a bit boring