leetcode_reverse_integer

Problem description:

Reverse digits of an integer.

Example1: x = 123, return 321
Example2: x = -123, return -321

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Note:
The input is assumed to be a 32-bit signed integer. Your function should return 0 when the reversed integer overflows.

My solution:

class Solution(object):    def reverse(self, x):        k = 2**31-1        if x >= 0:            b = str(x)            b1 = int(b[::-1])            if b1 > k:                return 0            elif b1 < -k:                return 0            else:                return int(b1)        elif x < 0:            c = str(x)            d = c[1:len(c)]            e = d[::-1]            f = c[0] + e            f1 = int(f)            if f1 > k:                return 0            elif f1 < -k:                return 0            else:                return  f1        """        :type x: int        :rtype: int        """

becsause 32-bit signed integer,so k=2**31-1