Java 扫雷 StackOverFlowError 递归

Question

我正在尝试制作一个控制台版本的扫雷。

尽管我目前很努力，但我无法弄清楚扫雷的“洪水填充”部分，如果所选方格的周围邻居不包含炸弹，我们现在必须检查这些相邻方格以找到相邻方格炸弹。

下面的代码适用于所选方 block 与炸弹相邻的情况:

// checking the adjacent cells, I made -1 = to the bomb value, rest of the cells
// are default(0)
public void sweep(int r, int c) {

    if (r < 0 || r >= grid.length || c < 0 || c >= grid[0].length) 
        return;

    int minRow = 0, minCol = 0, maxRow = 0, maxCol = 0, neighborBomb = 0;


    // means if I clicked a bomb, end the program
    if (grid[r][c] == -1) {
        System.out.println("Your selection [" + r + ", " + c + "] contained a bomb. .\nGAME OVER");
        System.exit(0);
    }

    // Series of if/else to find the min & max row col size to avoid going out of
    // bounds
    if (r == 0)
        minRow = 0;
    else
        minRow = r - 1;

    if (r == grid.length - 1)
        maxRow = r;
    else
        maxRow = r + 1;

    if (c == 0)
        minCol = 0;

    else
        minCol = c - 1;

    if (c == grid[0].length - 1)
        maxCol = c;
    else
        maxCol = c + 1;
    //if the selected cell is 0 & has not been searched yet.
    if (grid[r][c] == 0 && recurseSearch[r][c] == false) {

        recurseSearch[r][c] = true;
        // search adjacent cells to see how many bombs surround the cell in question
        neighborBomb = 0;
        for (int row = minRow; row <= maxRow; row++) {

            for (int col = minCol; col <= maxCol; col++) {

                if (grid[row][col] == -1) {
                    neighborBomb++;
                }

            }
        }
    }
        // cell will now display how many bombs are adjacent
        if (neighborBomb > 0) {
            grid[r][c] = neighborBomb;
            return;
        }
        //HERE I WANT TO CHECK ALL ADJACENT SQUARES BUT IT WILL ONLY RUN
        //sweep(r+1, c) rather than all the surrounding squares
        else {
            sweep(r + 1, c);
            sweep(r - 1, c);
            sweep(r + 1, c + 1);
            sweep(r + 1, c - 1);
            sweep(r - 1, c + 1);
            sweep(r - 1, c - 1);
            sweep(r, c + 1);
            sweep(r, c - 1);
        }
}

grid[][] 本质上是我的游戏板，recurseSearch[][] 是一个 boolean 值，它将跟踪单元格是否已被搜索。 if/else 语句的困惑是我试图不得到任何 IndexOutOfBoundErrors。 当我尝试运行并选择一个没有被炸弹包围的单元格时，我得到

   Exception in thread "main" java.lang.StackOverflowError

它会重复以下行

   sweep(r + 1, c);
   sweep(r - 1, c);

任何想法/建议都会有助于如何使我的递归实际检查所选原始 r,c 的每个相邻单元格!

Answer 1

您在检查后递归调用您的方法

//if the selected cell is 0 & has not been searched yet.
if (grid[r][c] == 0 && recurseSearch[r][c] == false) {
    recurseSearch[r][c] = true;
   // ...
}

因此，您对已访问过的字段重复递归，

但是递归只能发生在这个 if block 内。