LeetCode OJ算法题（七）：Reverse Integer

题目：

Reverse digits of an integer.

Example1: x = 123, return 321
Example2: x = -123, return -321

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Have you thought about this?
Here are some good questions to ask before coding. Bonus points for you if you have already thought through this!
If the integer's last digit is 0, what should the output be? ie, cases such as 10, 100.
Did you notice that the reversed integer might overflow? Assume the input is a 32-bit integer, then the reverse of 1000000003 overflows. How should you handle such cases?
Throw an exception? Good, but what if throwing an exception is not an option? You would then have to re-design the function (ie, add an extra parameter).

解法：

这题本身没什么难的，基本思想是把int转换成字符数组，根据有无符号进行逆序，最后再把字符数组转换成int。

这里直接调用了java的api将char[]转换为int，可以解决1000逆序后不应该出现0的问题

需注意，输入原则上允许超过int上界，因为是用字符串处理，而输出若超过int上界，则无法解析出int数据