func_code_string: #include <bits/stdc++.h>   const int inf = 1e9 + 7;   const int mod = 1e9 + 7;   using namespace std;   int main() {     long long N;     cin >> N;     long long cnt = 1;     long long now = 10;     while (now <= N) {       now *= 10;       cnt++;     }     long long ans = (cnt - 1) * 9;     long long n = cnt - 1;     long long sum = 0;     while (n--) {       sum = sum * 10 + 9;     }     sum = N - sum;     while (sum) {       ans += sum % 10;       sum /= 10;     }     cout << ans << endl;     return 0;   }   