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// #pragma GCC optimize("O3")
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#include <bits/stdc++.h>
using namespace std;

#define PB emplace_back
#define int long long
#define ll long long
#define vi vector<int>
#define siz(a) ((int) ((a).size()))
#define rep(i, a, b) for (int i = (a); i <= (b); ++i)
#define per(i, a, b) for (int i = (a); i >= (b); --i)
void print(vi n) { rep(i, 0, siz(n) - 1) cerr << n[i] << " \n"[i == siz(n) - 1]; }

const int N = 5e5;
int a, s[N + 5];

signed main() {
	// freopen(".in", "r", stdin);
	// freopen(".out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0), cout.tie(0);
	cin >> a;
	int x;
	rep(i, 1, a) cin >> x, ++s[x];
	vi t;
	rep(i, 1, a) if(s[i]) t.PB(s[i]);
	sort(t.begin(), t.end(), greater<int>());
	int ans = 0;
	rep(i, 0, siz(t) - 1) {
		++ans;
		int x = t[i] - 1;
		while(i != siz(t) - 1 && x) {
			--t.back();
			if(!t.back()) t.pop_back();
			--x;
		}
	}
	cout << ans;
	return cerr << endl << 1.0 * clock() / CLOCKS_PER_SEC << endl, 0;
}