Thread: tic tac toe AI

How would I check if the user gets 3 in a row in a tic tac toe game? I'm stumped

Here is the code I have:

Code:

#include <iostream>
#include <time.h>
#include <windows.h>
using namespace std;

void draw(char board[3][3])
{
	for(int i = 0; i < 3; i ++)
	{
		for(int t = 0; t < 3; t ++)
		{
			cout << board[i][t] << ' ';
		}

		cout << endl;
	}
}

void moveEnemey(char board[3][3], char icon[2])
{
	srand(time(NULL));

	int i, t;

	while(1)
	{
		i = rand()%3;
		t = rand()%3;

		if(board[i][t] == '_')
		{
			board[i][t] = icon[1];
			break;
		}
	}
}

int main()
{
	int input;

	char icon[2] = { 'X', 'O' };
	char board[3][3] = 
	{
		'_', '_', '_',
		'_', '_', '_',
		'_', '_', '_'
	};

	while(1)
	{
		draw(board);

		cout << "\nMake your move: ";
		cin >> input;

		if(board[0][input - 1] != icon[1])
		{
			board[0][input - 1] = icon[0];
			moveEnemey(board, icon);
		}
		else cout << '\a';

		system("cls");
	}

	return 0;
}

You want the code to step through and check all 8 possible rows of three in the grid. That's 3 horizontal, 3 vertical and 2 diagonal. As it does so, it needs to check for all 3 places being occupied by whichever piece the user is playing '0' or 'X'. You could either do this 'on the fly' and simply step through each route incrementing a counter and checking if the counter equals 3 at the end or maybe you will find it easier to load each 3 in a row path into a seperate array before checking the arrays. There are no doubt countless more and better ways to do it but these are 2 simple ones that spring to mind.

>>srand(time(NULL));
You should only call srand() once in your program, so move it to the start of main().

Code:

bool checkUserWin(char board[3][3], char icon[2])
{
	int counter = 0, counter2 = 0;

	while(counter2 <= 3)
	{
		for(int i = 0; i < 3; i ++)
		{
			if(board[counter2][i] == icon[0]) counter ++;
		}

		if(counter == 3) return TRUE;

		counter = 0;
		counter2 ++;
	}

	return FALSE;
}

This code only accounts for the top row (board[0][i])...any reason why it would do this?

Thanks, I got alot of of that!