Medium
Rotate Image — Python
Full explanation · Time O(n^2) · Space O(1)
# Time: O(n^2)
# Space: O(1)
class Solution(object):
# @param matrix, a list of lists of integers
# @return a list of lists of integers
def rotate(self, matrix):
n = len(matrix)
# anti-diagonal mirror
for i in xrange(n):
for j in xrange(n - i):
matrix[i][j], matrix[n-1-j][n-1-i] = matrix[n-1-j][n-1-i], matrix[i][j]
# horizontal mirror
for i in xrange(n / 2):
for j in xrange(n):
matrix[i][j], matrix[n-1-i][j] = matrix[n-1-i][j], matrix[i][j]
return matrix
# Time: O(n^2)
# Space: O(n^2)
class Solution2(object):
# @param matrix, a list of lists of integers
# @return a list of lists of integers
def rotate(self, matrix):
return [list(reversed(x)) for x in zip(*matrix)]