rustgym 0.2.0

struct Solution;

use std::collections::VecDeque;

struct Point {
    i: usize,
    j: usize,
}

macro_rules! point {
    ($i:expr,$j:expr) => {
        Point { i: $i, j: $j }
    };
}

impl Point {
    fn adj(&self, n: usize, m: usize) -> Vec<Point> {
        let mut res: Vec<Point> = vec![];
        for i in -1..=1 {
            for j in -1..=1 {
                let r = self.i as i32 + i;
                let c = self.j as i32 + j;
                if r < 0 || r > (n - 1) as i32 || c < 0 || c > (m - 1) as i32 {
                    continue;
                }
                res.push(point!(r as usize, c as usize))
            }
        }
        res
    }
}

impl Solution {
    fn update_board(mut board: Vec<Vec<char>>, click: Vec<i32>) -> Vec<Vec<char>> {
        let n = board.len();
        let m = board[0].len();
        let i = click[0] as usize;
        let j = click[1] as usize;
        if board[i][j] == 'M' {
            board[i][j] = 'X';
            return board;
        }
        let mut visited: Vec<Vec<bool>> = vec![vec![false; m]; n];
        let mut queue: VecDeque<Point> = VecDeque::new();
        queue.push_back(Point { i, j });
        while let Some(p) = queue.pop_front() {
            visited[p.i][p.j] = true;
            if board[p.i][p.j] == 'E' {
                let mut sum = 0;
                for q in p.adj(n, m) {
                    if board[q.i][q.j] == 'M' {
                        sum += 1;
                    }
                }
                if sum == 0 {
                    board[p.i][p.j] = 'B';
                    for q in p.adj(n, m) {
                        if !visited[q.i][q.j] {
                            queue.push_back(q);
                        }
                    }
                } else {
                    board[p.i][p.j] = (b'0' + sum) as char;
                }
            }
        }
        board
    }
}

#[test]
fn test() {
    let board = vec_vec_char![
        ['E', 'E', 'E', 'E', 'E'],
        ['E', 'E', 'M', 'E', 'E'],
        ['E', 'E', 'E', 'E', 'E'],
        ['E', 'E', 'E', 'E', 'E']
    ];
    let click = vec![3, 0];
    let res = vec_vec_char![
        ['B', '1', 'E', '1', 'B'],
        ['B', '1', 'M', '1', 'B'],
        ['B', '1', '1', '1', 'B'],
        ['B', 'B', 'B', 'B', 'B']
    ];
    assert_eq!(Solution::update_board(board, click), res);
}