Dart -如何在一定的难度范围内开始我的Tic Tac Toe游戏(简单)

import 'dart:io';

void main() {
  List<List<String>> board = [
    [' ', ' ', ' '],
    [' ', ' ', ' '],
    [' ', ' ', ' ']
  ];

  bool isPlayer1Turn = true;
  bool gameOver = false;

  while (!gameOver) {
    printBoard(board);

    String currentPlayer = isPlayer1Turn ? 'Player 1' : 'Player 2';
    stdout.write('$currentPlayer, enter your move (row column): ');
    String input = stdin.readLineSync() ?? '';
    List<String> move = input.split(' ');

    int row = int.tryParse(move[0]) ?? -1;
    int col = int.tryParse(move[1]) ?? -1;

    if (row >= 0 && row < 3 && col >= 0 && col < 3 && board[row][col] == ' ') {
      board[row][col] = isPlayer1Turn ? 'X' : 'O';
      isPlayer1Turn = !isPlayer1Turn;

      if (checkWin(board, row, col)) {
        printBoard(board);
        print('$currentPlayer wins!');
        gameOver = true;
      } else if (isBoardFull(board)) {
        printBoard(board);
        print('It\'s a tie!');
        gameOver = true;
      }
    } else {
      print('Invalid move. Try again.');
    }
  }
}

void printBoard(List<List<String>> board) {
  for (int i = 0; i < 3; i++) {
    print(' ${board[i][0]} | ${board[i][1]} | ${board[i][2]} ');
    if (i < 2) print('-----------');
  }
}

bool checkWin(List<List<String>> board, int row, int col) {
  String player = board[row][col];

  // Check row
  if (board[row][0] == player && board[row][1] == player && board[row][2] == player) {
    return true;
  }

  // Check column
  if (board[0][col] == player && board[1][col] == player && board[2][col] == player) {
    return true;
  }

  // Check diagonals
  if ((board[0][0] == player && board[1][1] == player && board[2][2] == player) ||
      (board[0][2] == player && board[1][1] == player && board[2][0] == player)) {
    return true;
  }

  return false;
}

bool isBoardFull(List<List<String>> board) {
  for (int i = 0; i < 3; i++) {
    for (int j = 0; j < 3; j++) {
      if (board[i][j] == ' ') {
        return false;
      }
    }
  }
  return true;
}