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#include <bits/stdc++.h>

using namespace std;
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())

template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) {
    return o << '(' << p.first << ", " << p.second << ')';
}

template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
    o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e;
    return o << '}';
}

#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n';
#else
#define debug(...) {}
#endif


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, x;
    cin >> n;
    vector<int> occs(n + 1), groups(n + 1);
    REP(i, n) {
        cin >> x;
        occs[x]++;
    }
    FOR(i, 1, n) {
        if (occs[i] != 0)
            groups[occs[i]]++;
    }

    vector<int> leads;
    FOR(i, 1, n) {
        while (groups[i] != 0) {
            groups[i]--;
            leads.emplace_back(i);
        }
    }

    int ans = 0;
    int l = 0, r = ssize(leads) - 1;
    while (l <= r) {
        ans++;
        int budget = leads[r] - 1;
        while (budget > 0 && l < r) {
            if (leads[l] > budget) {
                leads[l] -= budget;
                budget = 0;
            }
            else {
                budget -= leads[l];
                l++;
            }
        }
        r--;
    }

    cout << ans << '\n';

    return 0;
}