Question Link:

https://leetcode.com/problems/reverse-integer/

Solution

Use integer division and mod operations. The other thing is to take care the signed integer overflow.

Implementation

[-] Python code accepted by LeetCode OJ 
class Solution(object):
    def reverse(self, x):
        """
        :type x: int
        :rtype: int
        """
        # Signed int32 overflow
        MAX_SIGNED_INT = 2147483647

        if x < 0:
            n = -x
        else:
            n = x
        
        res = 0
        while n > 0:
            res = res * 10 + n % 10
            n = int(n * 0.1)
            if res > MAX_SIGNED_INT:
                return 0
                
        if x < 0:
            return -res
        else:
            return res