func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     long long n;     cin >> n;     long long a = 0;     long long ret = 0;     long long x = n;     while (x >= 10) {       a = a * 10 + 9;       ret += 9;       x /= 10;     }     long long y = n - a;     while (y) {       ret += y % 10;       y /= 10;     }     cout << ret << endl;   }   