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#include <bits/stdc++.h>

#define MAX_N 500007

using namespace std;

int n, k, t[MAX_N];
vector<int> v_sum;
int res;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> k;
        t[k]++;
    }
    
    for (int i = 1; i <= n; i++) {
        if (t[i] > 0) {
            v_sum.push_back(t[i]);
        }
    }
    sort(v_sum.begin(), v_sum.end(), greater<int>());
    for (auto v : v_sum) {
        n -= 2 * v - 1;
        res++;
        if (n <= 0) {
            break;
        }
    }
    cout << res;

    return 0;
}