Gray Code LeetCode solution in Python

1
import math
2

3

4
class Solution(object):
5
    def grayCode(self, n):
6
        """
7
        :type n: int
8
        :rtype: List[int]
9
        """
10
        allowedDiffs = [int(1 * math.pow(2, i)) for i in range(0, n)]
11
        grayCodes = [0]
12
        for diff in allowedDiffs:
13
            grayCodes += [code + diff for code in reversed(grayCodes)]
14
        return grayCodes