func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(nullptr);     cout.tie(nullptr);     cerr.tie(nullptr);     int n, res = 0, t, b;     cin >> n;     while (n) {       res++;       t = n;       b = -1;       while (t) {         b = max(b, t % 10);         t /= 10;       }       n -= b;     }     cout << res << endl;     return 0;   }   