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// Author: Bartek Knapik

#include <cstdio>

const int MAX_N = 500000 + 9;

struct Pair
{
    int val;
    int cnt;
    
    bool operator<(const Pair &oth) const {
        return cnt > oth.cnt;
    }
};

Pair leaders[MAX_N], tmp[MAX_N];
int n, val, n_leader;
int counter[MAX_N];

void sort(int begin, int end)
{
    if (end - begin <= 1) return;
    
    int mid = (begin + end) / 2;
    
    sort(begin, mid);
    sort(mid, end);
    
    int a = begin;
    int b = mid;
    int c = 0;
    
    while (a < mid && b < end)
    {
        if (leaders[a] < leaders[b]) tmp[c++] = leaders[a++];
        else tmp[c++] = leaders[b++];
    }
    
    while (a < mid) tmp[c++] = leaders[a++];
    
    while (b < end) tmp[c++] = leaders[b++];
    
    c = 0;
    
    while (begin < end) leaders[begin++] = tmp[c++];
}

int solve()
{
    scanf("%d", &n);
    for (int i = 0; i < n; ++i)
    {
        scanf("%d", &val);
        counter[val]++;
    }
    
    for (int i = 0; i < MAX_N; ++i)
        if (counter[i]) leaders[n_leader++] = { i, counter[i] };
    
    sort(0, n_leader);
    
    int ans, todo, begin, end, toremove;
    
    ans = 0;
    todo = n;
    begin = 0;
    end = n_leader - 1;
    
    while (todo)
    {
        ans++;
        if (leaders[begin].cnt > todo / 2) break;
        todo -= 2 * leaders[begin].cnt - 1;
        toremove = leaders[begin].cnt - 1;
        while (toremove)
        {
            if (leaders[end].cnt <= toremove)
            {
                toremove -= leaders[end].cnt;
                leaders[end].cnt = 0;
                end--;
            }
            else
            {
                leaders[end].cnt -= toremove;
                toremove = 0;
            }
        }
        begin++;
    }
    
    return ans;
}



int main()
{
    printf("%d\n", solve());
    
    return 0;
}