func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long N = 3e5 + 5;   const long long INF = 1e18;   const long long mod = 1e9 + 7;   void solve() {     long long n, m, k;     string s;     cin >> n;     map<int, int> F;     while (true) {       F[n] = 1;       n = n + 1;       while (n % 10 == 0) n /= 10;       if (F.find(n) != F.end()) break;     }     cout << F.size();   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     int t;     t = 1;     while (t--) solve();     return 0;   }   