#include <bits/stdc++.h>
using namespace std;
int s[110];
int main() {
  int n, tmp, sum = 0, cnt = 0;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> tmp;
    s[tmp]++;
  }
  int i = 0;
  for (; i <= 100; i++) {
    if (s[i] != 0) {
      tmp = 0;
      if (i == 0)
        cnt = s[i];
      else
        while (tmp < s[i]) {
          tmp++;
          if ((i + 1) * cnt < tmp + sum) cnt++;
        }
      sum += s[i];
    }
  }
  cout << cnt << endl;
  return 0;
}
