[LeetCode] Reverse Integer

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

简单题, 要注意结尾是0的情况的处理. 真沙茶同学什么时候才可以如此轻松的切难题呢.

class Solution {
public:
    
    long long myPow(int n, int p) {
        long long re = 1;
        for (int i = 0; i < p; ++i) {
            re *= n; 
        }
        return re;
    }

    int reverse(int x) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
        vector<int> vec;
        int t = x > 0 ? x : -x;
        int flag = 0;
        while (t) {
            int s = t % 10;
            if (s != 0) {
                flag = 1;
                vec.push_back(s);
            } else if(flag) {
                vec.push_back(s);
            }
            t /= 10;
        }
        long long re = 0;
        for (unsigned int i = 0; i < vec.size(); ++i) {
            re += vec[i] * myPow(10, (vec.size() - i -1));
        }
        return (x > 0 ? re : -re);
    }
};