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

Example 1:Input: 123Output: 321

Example 2:Input: -123Output: -321

Example 3:Input: 120Output: 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.

class Solution:    def reverse(self, x):        """        :type x: int        :rtype: int        """        flag = True        if x < 0:            flag = False            x = -x        temp = []        while x!=0:            temp.append(x%10)            x = int(x/10)        for i in range(len(temp)):            x = x*10+temp[i]        if flag == False:            x = -x        if x >= 2**31-1 or x <= -2**31:            return 0        return x

注意判断大小是否超出是判断转换之后的数字。

ps.才知道博客园也可以用markdown的