Leetcode_016 Letter Combinations of a Phone Number

这一题比较简答，但是这么简单的题我都敲了30多分钟，结果还有问题，修改，最后花了1个小时。。。。只能感叹自己水平太渣了，不熟练

class Solution {public:    vector<string> letterCombinations(string digits) {        vector<string> svec{ " ","", "abc","def","ghi","jkl","mno","pqrs","tuv","wxyz" };vector<string> resultvec;for (int i = 0; i < digits.size(); ++i)combin(svec[digits[i] - '0'], resultvec);return resultvec;    }private:    void combin(string s, vector<string> &svec){if (svec.empty()){string temp;for (int i = 0; i < s.size(); ++i)svec.push_back(temp + s[i]);return;}vector<string> ss;for (int time = 0; time < s.size(); ++time){vector<string> temp;for (vector<string>::iterator ite = svec.begin(); ite != svec.end(); ++ite)temp.push_back(*ite + s[time]);ss.insert(ss.begin(), temp.begin(), temp.end());}svec = ss;}};