题解 | #迷宫问题#

import java.util.*;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int m = in.nextInt();
        int n = in.nextInt();

        int[][] arr = new int[m][n];

        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                arr[i][j] = in.nextInt();
            }
        }

        List<int[]> res = new ArrayList<>();

        boolean[][] used = new boolean[m][n];
        bfs(res, arr, used, 0, 0);

        // for (int[] step : res) {
        //     System.out.println("(" + step[0] + "," + step[1] + ")");
        // }
    }

    private static void bfs(List<int[]> res, int[][] arr, boolean[][] used, int row,
                            int col) {
        if (!valid(arr, row, col)) {
            return;
        }

        if (row == arr.length - 1 && col == arr[0].length - 1) {
            res.add(new int[] {row, col});
            for (int[] step : res) {
                System.out.println("(" + step[0] + "," + step[1] + ")");
            }
            return;
        }

        if (used[row][col]) {
            return;
        }

        if (arr[row][col] == 0) {
            used[row][col] = true;
            res.add(new int[] {row, col});
            bfs(res, arr, used, row + 1, col);
            bfs(res, arr, used, row - 1, col);
            bfs(res, arr, used, row, col + 1);
            bfs(res, arr, used, row, col - 1);
            res.remove(res.size() - 1);
            used[row][col] = false;
        }
    }

    private static boolean valid(int[][] arr, int row, int col) {
        if (row < 0 || row >= arr.length || col < 0 || col >= arr[0].length) {
            return false;
        }

        if (arr[row][col] == 1) {
            return false;
        }

        return true;
    }
}