# -*- coding: utf-8 -*-

class Solution:

"""

@param matrix: A list of lists of integers

@return: Nothing

"""

def rotate(self, matrix):

# write your code here

rows = len(matrix)

'''

原始矩阵和目标矩阵为

1 2 3 7 4 1

4 5 6 => 8 5 2

7 8 9 9 6 3

先对非对角线元素做行列转置，实际只要做上半三角。

1 4 7

2 5 8

3 6 9

然后左右往当中列互换即可。

'''

if rows > 1:

for i in xrange(rows):

for j in xrange(i + 1, rows):

matrix[i][j], matrix[j][i] = matrix[j][i], matrix[i][j]

i, j = 0, rows - 1

while i < j:

for k in xrange(rows):

matrix[k][i], matrix[k][j] = matrix[k][j], matrix[k][i]

i += 1

j -= 1

return matrix