#include <bits/stdc++.h>   using namespace std;   int piles = 1, heavy = 0, num;   int a[110], n;   void solve(int x) {     if (num == 0) {       return;     }     if (heavy <= a[x]) {       a[x] = -1;       heavy++;       num--;       solve(x + 1);     } else if (x < n) {       solve(x + 1);     } else {       for (int i = 1; i <= n; i++) {         if (a[i] != -1) {           a[i] = -1;           num--;           heavy = 1;           piles++;           break;         }       }       solve(1);     }   }   int main() {     cin >> n;     num = n;     for (int i = 1; i <= n; i++) {       cin >> a[i];     }     for (int i = 2; i <= n; i++) {       for (int j = 1; j <= i; j++) {         if (a[i] < a[j]) {           swap(a[i], a[j]);         }       }     }     solve(1);     cout << piles;     return 0;   }   