LeetCode/rs/minimum-falling-path-sum.rs

impl Solution {
    fn get(matrix: &[Vec<i32>], row: isize, col: isize) -> Option<i32> {
        let rows = matrix.len() as isize;
        if row < 0 || row >= rows {
            return None;
        }

        let cols = matrix[row as usize].len() as isize;
        if col < 0 || col >= cols {
            return None;
        }

        Some(matrix[row as usize][col as usize])
    }

    pub fn min_falling_path_sum(mut matrix: Vec<Vec<i32>>) -> i32 {
        for row in (0..matrix.len() - 1).rev() {
            for col in 0..matrix[row].len() {
                matrix[row][col] += vec![-1, 0, 1]
                    .into_iter()
                    .filter_map(|dcol| Self::get(&matrix, row as isize + 1, col as isize + dcol))
                    .min()
                    .unwrap()
            }
        }

        *matrix.first().unwrap().iter().min().unwrap()
    }
}