Java 不可达语句 Tic Tac Toe

Question

import java.util.Scanner;

public class TTT{
public static int row, col;
public static Scanner scan = new Scanner(System.in);
public static char[][] board = new char[3][3];
public static char turn = 'X';

public static void main(String args[]){

 for(int i = 0; i < 3; i++){
   for(int j = 0; j < 3; j++){
     board[i][j] = '_';
   }
 }

 Play();


}
public static void Play(){
 boolean playing = true;
 printBoard();
 while(playing){
   System.out.println("Enter a row(1,2,3): ");
   row = scan.nextInt() - 1;
   System.out.println("Enter a column(1,2,3): ");
   col = scan.nextInt() - 1;
   board[row][col] = turn;
   if (GameOver(row, col)){
     playing = false;
     System.out.println("Game Over! Player " + turn + " wins!");  

   }
   if (turn == 'X')
     turn = 'O';
   else
     turn = 'X';


  }
}
public static void printBoard(){
  for(int i = 0; i < 3;i++){
   System.out.println();
   for(int j = 0; j < 3; j++){
     if (j == 0)
       System.out.print("| ");
     System.out.print(board[i][j] + " | "); 

   }
 }
 System.out.println();

}
public static boolean GameOver(int xToken,int oToken){
 // Check perpendicular victory
 if (board[0][oToken] == board[1][oToken]
     && board[0][oToken] == board[2][oToken])
    return true;
 if (board[xToken][0] == board[xToken][1]
     && board[xToken][0] == board[xToken][2])
    return true;
 // Check diagonal victory
 if (board[0][0] == board[1][1] && board[0][0] == board[2][2]
     && board[1][1] != '_')
    return true;  
 if (board[0][2] == board[1][1] && board[0][2] == board [2][0]
     && board[1][1] != '_');
    return true;
 return false;

}
}

我正在尝试完成我的井字游戏板，但是我在最终返回时收到一条无法访问的声明 false；陈述。我也无法让我的程序经历整个 for 循环。请帮忙!

Answer 1

看看你的if条件

if (board[0][2] == board[1][1] && board[0][2] == board [2][0]
     && board[1][1] != '_');<--

您以 ; 结束您的声明因此最后 2 次返回成为必然结果。

如果你删除它；那你就没事了。

这就是我成为 {} 粉丝的原因。良好的编码实践是始终使用 {} 来表示 if else。