[OJ.leetcode] reverse-integer

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

Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 

  class Solution { public: int reverse(int x) { if(x < 10 && x > -10) return x; int result = 0; stringstream ss; ss << x; string res = ss.str(); if(x < 0) { std::reverse((++res.begin()),res.end()); } else { std::reverse(res.begin(),res.end()); } return atoi(res.c_str()); } };