class Solution:
    def reverse(self, x: int) -> int:
        org = x
        x = abs(x)
        res = int(str(x)[::-1])
        if org < 0:
            res *= -1
        if res < -(1 << 31) or res > (1 << 31) - 1:
            return 0
        return res

class Solution:
    def reverse(self, x: int) -> int:
        def rec(n: int, rev: int) -> int:
            if n == 0:
                return rev

            rev = rev * 10 + n % 10
            return rec(n // 10, rev)

        sign = -1 if x < 0 else 1
        x = abs(x)
        reversed_num = rec(x, 0)
        reversed_num *= sign
        if reversed_num < -(1 << 31) or reversed_num > (1 << 31) - 1:
            return 0

        return reversed_num

class Solution:
    def reverse(self, x: int) -> int:
        MIN = -2147483648  # -2^31,
        MAX = 2147483647  #  2^31 - 1

        res = 0
        while x:
            digit = int(math.fmod(x, 10))
            x = int(x / 10)

            if res > MAX // 10 or (res == MAX // 10 and digit > MAX % 10):
                return 0
            if res < MIN // 10 or (res == MIN // 10 and digit < MIN % 10):
                return 0
            res = (res * 10) + digit

        return res