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#include <bits/stdc++.h>
using namespace std;
const int n_max = 500005;
vector<int> arr(n_max,-1);
vector<int>occur(n_max,0);
long long diff=0;
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n,N;
    cin >> n;
    N = n;
    arr.resize(n,-1);
    for(int i=0;i<n;i++){
        cin >> arr[i];
        occur[arr[i]]++;
        if(occur[arr[i]] == 1) diff++;
    }
    sort(occur.rbegin(),occur.rend());
    int ans=0,i=0;
    while(N>0){
        ans++;
        if(i>diff) break;
        N-= 2 * occur[i] - 1;
        i++;
    }
    cout << ans;
    return 0;
}