[LeetCode]7. Reverse Integer

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

翻转数字：123--->321, -123--->-321，overflow就返回0

如果overflow的话就不可逆

public class Solution {
    public int reverse(int x) {
        int res = 0;
        while (x != 0) {
            int newRes = res * 10 + x % 10;
            if ((newRes - x % 10) / 10 != res) {
                return 0;
            }
            res = newRes;
            x /= 10;
        }
        return res;
    }
}