java - TicTacToe 数组越界

Question

嘿，我正在制作一个 TicTacToe 游戏，它检查每个索引的值“x”或“o”，并且它一直给我错误 java.lang.ArrayIndexOutOfBoundsException: 3 第一个 if 语句。有什么帮助可以说明为什么会发生这种情况吗？

public boolean checkRowsForWin(int usrBrd, int WinSeq) {
    int countX = 0;
    int countO = 0;

    for(int i = 0; i < usrBrd; i++) {
        for(int j = 0; i< usrBrd; j++) {
            if(board[i][j] == 'x') {
                countX++;
            }
            else if(board[i][j] == 'o') {
                countO++;
            }
            else {
                countX = 0;
                countO = 0;
            }
            if (countX >= WinSeq) {
                return true;
            }
            else if (countO >= WinSeq) {
                return true;
            }
        }
    }
    return false;
}

这是我初始化板的地方

    Scanner scnr = new Scanner (System.in);

    System.out.println("Tic-Tac-Toe!");
    System.out.println("How large would you like the board?(Must be greater 
    than 3)");
    int usrBrd = scnr.nextInt();
    if(usrBrd < 3) {
        System.out.println("Not a valid number, please try again");
        usrBrd = scnr.nextInt();
    }
    TicTacToe game = new TicTacToe(usrBrd);
    game.initializeBoard(usrBrd);
    System.out.println("What should the win sequence be? Write in form of 
    amount i.e \"3\"  ");
    int winSeq = scnr.nextInt();

这里是初始化板子的方法

public TicTacToe(int usrBrd) {
    board = new char[usrBrd][usrBrd];
    currentPlayerMark = 'x';
    initializeBoard(usrBrd);
}
public void initializeBoard(int usrBrd) {
    //loop rows
    for (int i = 0; i < usrBrd; i++) {
        //loop columns
        for(int j = 0; j < usrBrd; j++) {
            board[i][j] = '-';
        }
    }
}

Answer 1

你的错误出现在第二个for循环中

for(int j = 0; i< usrBrd; j++)

您总是检查 i < usrBrd 是否始终评估为 true，因为“i”永远不会在该 for 循环中递增。