7. Reverse Integer

Medium

Problem Description

7. Reverse Integer

Medium


Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-231, 231 - 1], then return 0.

Assume the environment does not allow you to store 64-bit integers (signed or unsigned).

 

Example 1:

Input: x = 123
Output: 321

Example 2:

Input: x = -123
Output: -321

Example 3:

Input: x = 120
Output: 21

 

Constraints:

  • -231 <= x <= 231 - 1

Solution

0007-reverse-integer.py

python
0007-reverse-integer.py
1class Solution: 2 def reverse(self, x: int) -> int: 3 s = str(x) 4 if s[0] == '-': 5 a=int('-' + s[:0:-1]) 6 return 0 if a<(-2**31) else a 7 else: 8 b=int(s[::-1]) 9 return 0 if b>(2**31-1) else b