AI in tictactoe (segmentation error)

[manudude03]

Out of sheer boredom, I decided to do the regular tictactoe game and try and make the computer unbeatable. I've got it to the point where it is drawing the majority of the time, but I am having some problems when I tell it to watch out for forks (where a line can be made in 2 different ways in the next move). I thought I had it working, but occasionally it clears the screen and goes into an infinite loop of blank lines. After about 15 mins of testing, I finally got a segmentation error. Here's the code (hope it's not too long)

#include <iostream>
#include <ctime>
#include <cstdlib>

using namespace std;

bool ComputerValidMove(char board[], int movemade)
{
    if (board[movemade]=='X'||board[movemade]=='O')
    {
        return false;
    }
    return true;
}
int LookForWin(char board[],char player[],int play, bool fork=false)
{
    int wincombos[8][3]={{0,1,2},{3,4,5},{6,7,8},{0,3,6},{1,4,7},{2,5,8},{0,4,8},{2,4,6}};
    for (int i=0; i<8; i++)
    {
        int pieces=0;
        int emptysquares=0;
        for (int j=0; j<3; j++)
        {
            if (board[wincombos[i][j]]==player[play])
            {
                pieces++;
            }
            else if (board[wincombos[i][j]]!='X' && board[wincombos[i][j]]!='O')
            {
                emptysquares++;
            }
        }
        if (pieces==2 && emptysquares==1)
        {
            for (int j=0; j<3; j++)
            {
                if (board[wincombos[i][j]]!='X' && board[wincombos[i][j]]!='O')
                {
                    return wincombos[i][j];
                }
            }
        }
        if (fork && pieces==1 && emptysquares==2)
        {
            for (int k=i+1; k<8; k++)
            {
            // find an intersecting line with the same property
                for (int j=0; j<3; j++)
                {
                    if (board[wincombos[k][j]]==player[play])
                    {
                        pieces++;
                    }
                    else if (board[wincombos[k][j]]!='X' && board[wincombos[k][j]]!='O')
                    {
                        emptysquares++;
                    }
                }
            }
            if (pieces==2 && emptysquares==4)
            {
                for (int j=0; j<3; j++)
                {
                    for (int k=i+1; k<8; k++)
                    {
                        for (int m=0; m<3; m++)
                        {
                            if (wincombos[i][j]==wincombos[k][m] && board[wincombos[i][j]]!='X' && board[wincombos[i][j]]!='O')
                            {
                                return board[wincombos[i][j]];
                            }
                        }
                    }
                }
            }
        }
    }
    return 9;
}
void DisplayBoard(char board[])
{
    for (int i=0; i<3; i++)
    {
        cout << "   |   |   " << endl;
        for (int j=0; j<3; j++)
        {
            cout << " " << board[3*i+j] << " ";
            if (j!=2)
            {
                cout << "|";
            }
        }
        cout << endl;
        if (i!=2)
        {
            cout << "___|___|___" << endl;
        }
    }
    cout << "   |   |   " << endl;
}
void ComputerMove (char board[],char player[], int& movesmade)
{
    int moves;
    string positions[9]={"top-left", "top-middle", "top-right", "middle-left", 
"center", "middle-right", "bottom-left", "bottom-middle", "bottom-right"};
    if (movesmade==0)
    {
        moves=rand()%9;
        board[moves]=player[1];
    }
    else if (movesmade==1)
    {
        if (board[0]==player[0]||board[2]==player[0]||board[6]==player[0]||board[8]==player[0])// if player went in corner
        {
            moves=4;
            board[moves]=player[1];
        }
        else if (board[4]==player[0])
        {
            bool validmove=false;
            while (!validmove)
            {
                int movelist[4]={0,2,6,8};
                moves=movelist[rand()%4];
                if (ComputerValidMove(board,moves))
                {
                    board[moves]=player[1];
                    validmove=true;
                }
            }
        }
    }
    else if (LookForWin(board , player, 1)!=9)
    {
        moves=LookForWin(board , player, 1);
        board[moves]=player[1];
    }
    else if (LookForWin(board , player, 0)!=9)
    {
        moves=LookForWin(board , player, 0);
        board[moves]=player[1];
    }
    else if (LookForWin(board , player, 1, true)!=9)
    {
        moves=LookForWin(board , player, 1,true);
        board[moves]=player[1];
    }
    else if (LookForWin(board , player, 0, true)!=9)
    {
        moves=LookForWin(board , player, 0,true);
        board[moves]=player[1];
    }
    else
    {
        bool validmove=false;
        while (!validmove)
        {
            moves=rand()%9;
            if (ComputerValidMove(board,moves))
            {
                board[moves]=player[1];
                validmove=true;
            }
        }
    }
    cout << "The computer took the " << positions[moves] << " square." << endl;
    movesmade++;
}
void PlayerMove (char board[],char player[], int turn, int& movesmade)
{
    string positions[9]={"top-left", "top-middle", "top-right", "middle-left", 
"center", "middle-right", "bottom-left", "bottom-middle", "bottom-right"};
    board[turn]=player[0];
    cout << "You took the " << positions[turn] << " square." << endl;
    movesmade++;
}
bool GameStatus(char board[], char player[], int& gameswon, int& gamesdrawn, int& gameslost)
{
    if (board[0]==board[1] && board[1]==board[2])
    {
        if (board[0]==player[1])
        {
            gameslost++;
            return true;
        }
        else
        {
            gameswon++;
            return true;
        }
    }
    else if (board[0]==board[3] && board[3]==board[6])
    {
        if (board[0]==player[1])
        {
            gameslost++;
            return true;
        }
        else
        {
            gameswon++;
            return true;
        }
    }
    else if (board[2]==board[5] && board[5]==board[8])
    {
        if (board[2]==player[1])
        {
            gameslost++;
            return true;
        }
        else
        {
            gameswon++;
            return true;
        }
    }
    else if (board[6]==board[7] && board[7]==board[8])
    {
        if (board[6]==player[1])
        {
            gameslost++;
            return true;
        }
        else
        {
            gameswon++;
            return true;
        }
    }
    for (int i=0; i<4; i++)
    {
        if (board[4]==board[i] && board[4]==board[8-i])
        {
            if (board[4]==player[1])
            {
                gameslost++;
                return true;
            }
            else
            {
                gameswon++;
                return true;
            }
        }
    }
    for (int i=0; i<9; i++)
    {
        if (board[i]!='X' && board[i]!='O')
        {
            return false;
        }
    }
    gamesdrawn++;
    return true;
}

D'oh, code was too long, will post the main function in next post. Here's the errors I'm getting:

#0 0046A91D std::basic_ostream<char, std::char_traits<char> >& std::operator<< <char, std::char_traits<char>, std::allocator<char> >(std::basic_ostream<char, std::char_traits<char> >&, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) () (??:??)
#1 00478860 std::cerr () (??:??)
#2 0046F0A5 std::__convert_from_v () (??:??)
#3 00402BD7 main() (C:\C++ Game\tictactoe\main.cpp:329)

[manudude03]

int main()
{
    srand ( unsigned (time(0) ) );
    bool programactive=true;
    char board[9]={'1', '2', '3', '4', '5', '6', '7', '8', '9'};
    int playermove;
    int gameswon=0;
    int gamesdrawn=0;
    int gameslost=0;
    int gamesplayed=0;
    char piece;
    char player[2];
    int movesmade;
    bool gameactive;
    while (piece!='X' && piece!='O')
    {
        cout << "Select your piece (X or O)" << endl;
        cin >> piece;

    }
    if (piece=='X')
    {
        player[0]='X';
        player[1]='O';
    }
    else
    {
        player[0]='O';
        player[1]='X';
    }
    while (programactive)
    {
        for (int i=0; i<9; i++)
        {
            board[i]=i+49; // sets positions to 1-9 (ASCII code)
        }
        cout << "W: " << gameswon << " D: " << gamesdrawn << " L: " << gameslost << endl;
        gameactive=true;
        movesmade=0;
        while (gameactive)
        {
            if (gamesplayed%2==0 && movesmade==0)
            {
                ComputerMove(board, player, movesmade);
            }
            DisplayBoard(board);
            bool playerturn=false;
            if (!GameStatus(board, player, gameswon, gamesdrawn, gameslost))
            {
                cout << "Make your move." << endl;
                while (!playerturn)
                {
                    cin >> playermove;
                    if (playermove>9 || playermove<0 || board[playermove-1]=='X' || board[playermove-1]=='O')
                    {
                        cout << "invalid move- please select another" << endl;
                    }
                    else
                    {
                        PlayerMove(board, player, playermove-1, movesmade);
                        playerturn=true;
                    }
                }
            }
            else
            {
                gameactive=false;
                DisplayBoard(board);
                break;
            }
            if (!GameStatus(board, player, gameswon, gamesdrawn, gameslost))
            {
                ComputerMove(board, player, movesmade); // seg error here
            }
            else
            {
                gameactive=false;
                DisplayBoard(board);
                break;
            }
        }
        gamesplayed++;
    }
    return 0;
}