题目描述

blablabla

样例

blablabla

算法1

() $O(n^2)$

blablabla

时间复杂度分析：blablabla

Python 代码

class Solution(object):
    def printMatrix(self, matrix):
        """
        :type matrix: List[List[int]]
        :rtype: List[int]
        """
        if len(matrix) == 0:
            return []
        m = len(matrix)
        n = len(matrix[0])
        dx = [1, 0 , -1, 0]
        dy = [0, 1, 0, -1]
        res = []
        memo = [[False] * n]
        for _ in range(m):
            memo.append([False] * n)  # 直接[[False] * n] * m因为reference的问题不可行
        d = 0
        x, y = 0, 0
        for i in range(m * n):
            res.append(matrix[y][x])
            memo[y][x] = True
            xx = x + dx[d]
            yy = y + dy[d]
            if xx >= n or xx < 0 or yy < 0 or yy >= m or memo[yy][xx]:
                d = (d + 1) % 4
                xx = x + dx[d]
                yy = y + dy[d]
            x = xx
            y = yy

        return res