class Solution(): def reverse(self, x): # Note that in Python -1 / 10 = -1 res, isPos = 0, 1 if x < 0: isPos = -1 x = -1 * x while x != 0: res = res * 10 + x % 10 if res > 2147483647: return 0 x = int(x / 10) return res * isPos s = Solution() print (s.reverse(123))