class Solution:
    def reverse(self , num: int) -> int:
        # write code here
        a = 1
        b = str(num)
        if b[0] == "-":
            a = -1
            b = b[1:]
        c = b[::-1]
        d = a*int(c)
        if d >= 2**31-1 or d<=-2**31:
            return 0
        return d