Solution.rs

use std::collections::VecDeque;
impl Solution {
    pub fn shortest_path_binary_matrix(mut grid: Vec<Vec<i32>>) -> i32 {
        let n = grid.len();
        let mut queue = VecDeque::new();
        queue.push_back([0, 0]);
        let mut res = 0;
        while !queue.is_empty() {
            res += 1;
            for _ in 0..queue.len() {
                let [i, j] = queue.pop_front().unwrap();
                if grid[i][j] == 1 {
                    continue;
                }
                if i == n - 1 && j == n - 1 {
                    return res;
                }
                grid[i][j] = 1;
                for x in -1..=1 {
                    for y in -1..=1 {
                        let x = x + i as i32;
                        let y = y + j as i32;
                        if x < 0 || x == n as i32 || y < 0 || y == n as i32 {
                            continue;
                        }
                        queue.push_back([x as usize, y as usize]);
                    }
                }
            }
        }
        -1
    }
}