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/*
Things to notice:
1. do not calculate useless values
2. do not use similar names
 
Things to check:
1. submit the correct file
2. time (it is log^2 or log)
3. memory
4. prove your naive thoughts 
5. long long
6. corner case like n=0,1,inf or n=m
7. check if there is a mistake in the ds or other tools you use
8. fileio in some oi-contest

9. module on time 
10. the number of a same divisor in a math problem
11. multi-information and queries for dp and ds problems
*/
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
const int mod=998244353;
const int inf=0x3f3f3f3f;
int n,a[500005];
void solve()
{
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		int x;
		cin>>x;
		a[x]++;
	}
	multiset <int> S;
	for(int i=1;i<=n;i++) if(a[i]) S.insert(a[i]);
	int ans=0;
	while(S.size())
	{
		ans++;
		int x=(*prev(S.end()));
		S.erase(prev(S.end()));
		x--;
		while(S.size()&&x)
		{
			int y=(*S.begin());
			S.erase(S.begin());
			int d=min(x,y);
			x-=d,y-=d;
			if(y) S.insert(y);
		}
	}
	cout<<ans<<"\n";
}
signed main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	int _=1;
//	cin>>_;
	while(_--) solve();
	return 0;
}