func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long MOD = 1e9 + 7;   const int N = 1e5 + 7, M = 1e7, OO = 0x3f3f3f3f;   map<int, int> dp;   int solve(int num) {     if (num == 0) {       return 0;     }     if (dp[num]) {       return dp[num];     }     vector<int> v;     int temp = num;     while (temp) {       v.push_back(temp % 10);       temp /= 10;     }     int ret = -OO;     for (int i = 0; i < v.size(); ++i) {       ret = max(ret, v[i]);     }     return dp[num] = 1 + solve(num - ret);   }   int main() {     dp.clear();     int num;     cin >> num;     cout << solve(num);     return 0;   }   