#include <bits/stdc++.h>
using namespace std;
int main() {
  int a[105] = {0};
  int n;
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cin >> n;
  int temp, mx = 0;
  for (int i = 0; i < n; ++i) {
    cin >> temp;
    a[temp]++;
    mx = max(mx, temp);
  }
  for (int i = 1; i < mx + 1; ++i) a[i] += a[i - 1];
  for (int i = 0; i < mx + 1; ++i) {
    if ((a[i] % (i + 1)) == 0)
      a[i] /= (i + 1);
    else
      a[i] = (a[i] / (i + 1)) + 1;
  }
  int res = *max_element(a, a + 101);
  cout << res << "\n";
  return 0;
}
