#include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(0);     cin.tie(0);     int k;     cin >> k;     string s;     cin >> s;     long long tot = 0;     int av[11];     memset(av, 0, sizeof(av));     int ans = 0;     for (char a : s) tot += a -  0 , av[9 - (a -  0 )]++;     for (int i = 10; i; i--) {       if (tot >= k) break;       if (k - av[i] * i < tot) {         while (k > tot) {           k -= i;           ans++;         }         break;       } else {         k -= av[i] * i;         ans += av[i];       }     }     cout << ans <<   n ;   }   