48. Rotate Image

You are given an n x n 2D matrix representing an image.

Rotate the image by 90 degrees (clockwise).

Follow-Up:

Could you do this in-place?

Solution:

class Solution(object):
    def rotate(self, matrix):
        """
        :type matrix: List[List[int]]
        :rtype: void Do not return anything, modify matrix in-place instead.
        """
        matrix.reverse()
        for i in xrange(len(matrix)):
            for j in xrange(i + 1, len(matrix[i])):
                matrix[i][j], matrix[j][i] = matrix[j][i], matrix[i][j]