leetCode练题——7. Reverse Integer

1、题目：

 

7. Reverse Integer

Given a 32-bit signed integer, reverse digits of an integer.

Example 1:

Input: 123
Output: 321

Example 2:

Input: -123
Output: -321

Example 3:

Input: 120
Output: 21

Note:
Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−2³¹,  2³¹ − 1]. For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.

 

2、我的解法：

 # -*- coding: utf-8 -*-
 # @Time    : 2020/1/26 12:33
 # @Author  : SmartCat0929
 # @Email   : 1027699719@qq.com
 # @Link    : https://github.com/SmartCat0929
 # @Site    :
 # @File    : 7. Reverse Integer.py
 class Solution:
     def reverse(self, x: int) -> int:
         if x >= -2147483648 and x <= 2147483647:
             if x >= 0:
                 r = ""
             else:
                 r = "-"
             w = abs(x)
             y = str(w)
             n = len(y)
             d = []
             for i in (y):
                 d.append(i)
             for j in range(n):
                 c = d.pop()
                 r = r + c
                 v = int(r)
             if v >= -2147483648 and v <= 2147483647:
                 return v
             else:
                 return 0
         else:
             return 0