PAT甲级 1005. Spell It Right(20分)

12345
结尾无空行

one five
结尾无空行

#include <iostream>
#include <vector>
using namespace std;
int main()
{
    string words;
    cin >> words;
    int sum = 0;
    for (char it : words)
    {
        sum += atoi(&it);
    }
    string hash[10] = {"zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine"};
    string res = to_string(sum);
    cout << hash[res[0] - '0'];
    for (int i = 1; i < res.size(); i++)
    {
        int num = res[i] - '0';
        cout << " " << hash[num];
    }
    return 0;
}