题目
给你一个 m 行 n 列的矩阵 matrix ,请按照 顺时针螺旋顺序 ,返回矩阵中的所有元素。
示例
示例 1
输入:matrix = [[1,2,3],[4,5,6],[7,8,9]]
输出:[1,2,3,6,9,8,7,4,5]
示例 2
输入:matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]
输出:[1,2,3,4,8,12,11,10,9,5,6,7]
提示
php
m == matrix.length
n == matrix[i].length
1 <= m, n <= 10
-100 <= matrix[i][j] <= 100
思路
深搜,方向旋转。需要特别处理在最左边往上搜索的情况。
AC代码
rust
impl Solution {
pub fn dfs(v: &Vec<Vec<i32>>, vis: &mut Vec<Vec<bool>>, x: i32, y: i32) -> Vec<i32> {
let x_len = v.len() as i32;
let y_len = v[0].len() as i32;
let mut res: Vec<i32> = Vec::new();
if x < 0 || x >= x_len || y < 0 || y >= y_len || vis[x as usize][y as usize] {
return res;
}
vis[x as usize][y as usize] = true;
let mut res1: Vec<i32> = Vec::new();
let mut res2: Vec<i32> = Vec::new();
let mut res3: Vec<i32> = Vec::new();
let mut res4: Vec<i32> = Vec::new();
res1 = match x >= 1 && (y == 0 || (y >= 1 && vis[x as usize][y as usize - 1])) && !vis[x as usize - 1][y as usize]{
true => Solution::dfs(v, vis, x - 1, y),
_ => Solution::dfs(v, vis, x, y + 1)
};
res2 = Solution::dfs(v, vis, x + 1, y);
res3 = Solution::dfs(v, vis, x, y - 1);
res4 = Solution::dfs(v, vis, x - 1, y);
res.push(v[x as usize][y as usize]);
res.extend(res1);
res.extend(res2);
res.extend(res3);
res.extend(res4);
res
}
pub fn spiral_order(v: Vec<Vec<i32>>) -> Vec<i32> {
let x_len = v.len();
let y_len = v[0].len();
let mut vis: Vec<Vec<bool>> = vec![vec![false; y_len]; x_len];
Solution::dfs(&v, &mut vis, 0 , 0)
}
}