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#include <bits/stdc++.h>
#define ll long long
#define fast ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define pb push_back
#define f first
#define s second
#define pii pair<int, int>
#define pll pair<ll, ll>
using namespace std;
const int N = 5e5+1;
int n,cnt[N];
int main(){
    fast
    int n;
    cin >> n;
    for(int i = 0;i < n;i++){
        int a;
        cin >> a;
        cnt[a]++;
    }
    vector<int>cnt2;
    for(int i = 1;i <= n;i++)
        if(cnt[i] > 0)
            cnt2.pb(cnt[i]);
    sort(cnt2.begin(),cnt2.end());
    int a = 0,b = cnt2.size() - 1,res = cnt2.size();
    while(a < b){
        int ile = min(cnt2[a],cnt2[b]-1);
        cnt2[a] -= ile;
        cnt2[b] -= ile;
        if(cnt2[a] == 0){
            res--;
            a++;
        }
        if(cnt2[b]==1)
            b--;
    }
    cout << res << "\n";
}