添加链接描述

class Solution:def spiralOrder(self, matrix: List[List[int]]) -> List[int]:if not matrix or not matrix[0]:return list()rows, columns = len(matrix), len(matrix[0])order = list()left, right, top, bottom = 0, columns - 1, 0, rows - 1while left <= right and top <= bottom:for column in range(left, right + 1):order.append(matrix[top][column])for row in range(top + 1, bottom + 1):order.append(matrix[row][right])if left < right and top < bottom:for column in range(right - 1, left, -1):order.append(matrix[bottom][column])for row in range(bottom, top, -1):order.append(matrix[row][left])left, right, top, bottom = left + 1, right - 1, top + 1, bottom - 1return order

思路：

1. 按层进行遍历
2. 然后就是判断每个边界值的条件
3. 向左和下走是被允许的，向右或向上走是不被允许的需要条件判断
4. 个人认为这道题的实际意义不大，主要是吓唬人