48. Rotate Image.py

class Solution(object):
    def rotate(self, matrix):
        """
        :type matrix: List[List[int]]
        :rtype: None Do not return anything, modify matrix in-place instead.
        """
        #转置矩阵
        for i in range(len(matrix)):
            for j in range(i, len(matrix[i])):
                matrix[i][j], matrix[j][i] = matrix[j][i], matrix[i][j]

        #逐行翻转
        for i in range(len(matrix)):
            matrix[i].reverse()

        return matrix

class Solution:
    def rotate(self, matrix):
        """
        :type matrix: List[List[int]]
        :rtype: void Do not return anything, modify matrix in-place instead.
        """
        n = len(matrix[0])
        for i in range(n//2 + n%2):
            for j in range(n//2):
                tmp = matrix[n-1-j][i]
                matrix[n-1-j][i] = matrix[n-i-1][n-j-1]
                matrix[n-i-1][n-j-1] = matrix[j][n-i-1]
                matrix[j][n-i-1] = matrix[i][j]
                matrix[i][j] = tmp