func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long n, m, i;     cin >> n;     long long cnt = 0;     while (n >= 10) {       n++;       while (n % 10 == 0) {         n = n / 10;       }       cnt++;     }     cout << cnt + 9 << endl;   }   