我有这种方法确定给定行和列的电路板上的方块是否受到第1列到第1列中任何皇后的攻击。但我在电路板[行列+ y] [y] == QUEEN
上不断出现异常错误 private boolean isUnderAttack(int row, int column)
{
for (int y=0; y<column; y++)
{
if (board[row][y] == QUEEN || // possible horizontal attack
board[row-column+y][y] == QUEEN || // diagonal NW
board[row+column-y][y] == QUEEN) // diagonal SW
return true;
}
return false;
}
答案 0 :(得分:1)
row + column - y
此操作可以返回小于0的数字。
你的课应该是这样的:
import java.util.Arrays;
public class Board {
private final int[][] board;
private final int dimention;
public static void main(final String[] args) {
final Board p = new Board(6);
for (final int[] i : p.board) {
System.out.println(Arrays.toString(i));
}
p.isUnderAttack(2, 3);
System.out.println("\n\n");
for (final int[] i : p.board) {
System.out.println(Arrays.toString(i));
}
}
public Board(final int dimention) {
this.dimention = dimention;
this.board = new int[dimention][dimention];
}
private void isUnderAttack(final int row, final int column) {
for (int y = 0; y < this.dimention; y++) {
this.board[y][row] = 1; // possible horizontal attack
this.board[column][y] = 2; // possible vertical attack
}
int staringRow = column - row;
int y = 0;
do {
this.board[staringRow][y] = 3; // diagonal SW
} while ((++staringRow < this.dimention) && (++y < this.dimention));
int staringCol = column + row;
int x = 0;
do {
this.board[x][staringCol] = 4; // diagonal NW
} while ((++x < this.dimention) && (--staringCol < this.dimention));
}
}
这是此测试的输出:
[0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0]
[0, 0, 1, 0, 0, 4]
[3, 0, 1, 0, 4, 0]
[0, 3, 1, 4, 0, 0]
[2, 2, 4, 2, 2, 2]
[0, 4, 1, 3, 0, 0]
[4, 0, 1, 0, 3, 0]