题目
Reverse digits of an integer.
Example1: x = 123, return 321
Example2: x = -123, return -321
简单题，需要考虑两个问题，1）如果输入的末尾是0怎么办？2）如果倒过来的数字溢出了怎么办？
class Solution { public: int reverse(int x) { int flag = 1; unsigned res = 0;; if (x < 0){ flag = -1; x = flag * x; } while (x > 0) { if (res > (INT_MAX - x%10)/10) return 0; res = res*10 + x%10; x = x/10; } return flag * (int)res; } };
原文：http://www.cnblogs.com/Doctengineer/p/5858693.html