参考代码:

class Solution:
    def reverseInteger(self, n):
        if n == 0:
            return 0
        neg = 1
        if n < 0:
            neg, n = -1, -n
        revers = 0
        while n > 0:
            reverse = reverse * 10 + n % 10
            n = n // 10
        reverse = reverse * neg
        if reverse < - (1 << 31) or reverse > (1 << 31) - 1:
            return 0
        return reverse