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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

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

    int n;
    cin >> n;
    vector<int> c(n + 1, 0);

    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        c[a]++;
    }

    // for (auto &v : c) cout << v << ", ";
    // cout << "dupa\n";

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

    // for (auto &v : c) cout << v << ", ";
    // cout << "dupa\n";

    int i = 1;
    int j = n;
    int ans = 0;
    while (i <= j) {
        // cout << "iter\n";
        while (i <= j && c[j] == 0) --j;
        int cnt = c[j];
        if (c[j] == 0) break;
        
        // cout << j << endl;
        while (i < j && c[j] > 1) {
            if (c[i] == 0) {
                ++i;
                continue;
            }
            c[i]--;
            c[j]--;
        }
        ++ans;
        --j;
    }
    cout << ans << endl;
}