#include <iostream>
#include <algorithm>

using namespace std;

const int MAX_N = 500001;
int inp[MAX_N];
int tmp[MAX_N];
int yep[MAX_N];
int N;

int licz()
{
    for (int i = 1; i < MAX_N; i++)
    {
        if (inp[i] > 0) {
            tmp[inp[i]]++;
        }
    }

    int g = 0;
    for (int i = MAX_N - 1; i > 0; i--) {
        while(tmp[i]-->0){
            yep[g++] = i;
        }
    }
    int s = 0;
    int c = 0;

    while (s < N)
    {
        s += yep[c] * 2 - 1;
        c++;
    }
    return c;
}

int main()
{
    cin >> N;
    int x;
    for (int i = 0; i < N; i++)
    {
        cin >> x;
        inp[x]++;
    }
    cout << licz() << endl;
    return 0;
}