Python 解leetcode:48. Rotate Image

  • 题目描述:把一个二维数组顺时针旋转90度;
  • 思路:
  1. 对于数组每一圈进行旋转,使用m控制圈数;
  2. 每一圈的四个元素顺时针替换,可以直接使用Python的解包,使用k控制每一圈的具体元素;
class Solution(object):
    def rotate(self, matrix):
        """
        :type matrix: List[List[int]]
        :rtype: void Do not return anything, modify matrix in-place instead.
        """
        n = len(matrix)
        m = 0
        while m <= n / 2:
            k = m
            while k < n - 1 - m:
                matrix[m][k], matrix[k][n-1-m], matrix[n-1-m][n-1-k], matrix[n-1-k][m] = \
                    matrix[n-1-k][m], matrix[m][k], matrix[k][n-1-m], matrix[n-1-m][n-1-k]
                k += 1
            m += 1
时间: 2024-10-09 01:41:29

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