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#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

const int MAXN = 500100;

int main(int argc, char* argv[])
{
#ifdef _DEBUG
	freopen("input.txt", "rt", stdin);
	freopen("output.txt", "wt", stdout);
#endif
	static pair<int, int> valToNum[MAXN];
	memset(valToNum, 0x00, sizeof(valToNum));
	int n;
	scanf("%d", &n);
	for (int v = 1; v <= n; v++)
		valToNum[v].second = v;
	for (int i = 0; i < n; i++) {
		int v;
		scanf("%d", &v);
		valToNum[v].first++;
	}
	sort(valToNum + 1, valToNum + n + 1);
	int left = 1, right = n;
	int res = 0;
	while (left <= right) {
		int numOfLeaders = valToNum[right].first;
		int maxNonLeadersNow = numOfLeaders - 1;
		valToNum[right].first = 0;
		while (left < right && valToNum[left].first <= maxNonLeadersNow) {
			maxNonLeadersNow -= valToNum[left].first;
			valToNum[left].first = 0;
			left++;
		}
		if (left < right && maxNonLeadersNow > 0) {
			valToNum[left].first -= maxNonLeadersNow;
			if (valToNum[left].first < 0) {
#ifdef _DEBUG
				_DEBUG_ERROR("valToNum[left].first > 0");
#endif
				valToNum[left].first = 0;
			}
		}
		res++;
		right--;
	}
	printf("%d\n", res);
	return 0;
}