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#include <bits/stdc++.h>
using namespace std;


struct repr {
	int a;
	int cnt;

	repr(int x) : a(x), cnt(0) {}
};


bool operator<(const repr& x, const repr& y) {
	return (x.cnt == y.cnt) ? (x.a < y.a) : (x.cnt < y.cnt);
}


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

	int n;
	cin >> n;

	vector<int> a;
	a.reserve(n + 1);

	for (int i = 0; i < n; ++i) {
		int x;
		cin >> x;

		a.push_back(x);
	}

	sort(a.begin(), a.end());

	vector<repr> r;
	repr c = repr(a[0]);
	for (int i = 0; i < a.size(); ++i) {
		if (c.a != a[i]) {
			r.push_back(c);
			c = repr(a[i]);
		}

		c.cnt++;
	}

	if (c.cnt > 0)
		r.push_back(c);

	sort(r.begin(), r.end());

	int p = 0, q = r.size() - 1, res = 0;
	while (p < q) {
		while (p < q && r[q].cnt > 1) {
			int d = min(r[q].cnt - 1, r[p].cnt);
			r[p].cnt -= d;
			r[q].cnt -= d;

			if (r[p].cnt == 0)
				p++;
		}
		q--;
		res++;
	}

	if (p == q)
		res++;

	cout << res << endl;
}