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#include <algorithm>
#include <iostream>
#include <iomanip>
#include <map>
#define REP(x,n) for (int x=0;x<(n);++x)
#define VAR(x,n) __typeof(n) x = (n)
#define FOREACH(x,c) for(VAR(x,(c).begin()); x != (c).end(); ++x)
//#define __DEBUG

#define MAX_N 500001

using namespace std;

int n,i,m;
map<int,int> occurrencesByNumber;
int occurrencesOnly[MAX_N];

int solve() {
        cin >> n;
    REP(x,n) {
        cin>>i;
        ++occurrencesByNumber[i];
    }
    FOREACH(it,occurrencesByNumber) {
        occurrencesOnly[m++] = it->second;
    }
    std::sort(occurrencesOnly, occurrencesOnly+m, greater<int>());
#ifdef __DEBUG
    REP(x,m) {
        cerr << occurrencesOnly[x];
    }
#endif
    
    int sequences = 0;
    int leftItems = n;
    for (int* occurrence = occurrencesOnly; leftItems > 0; ++occurrence) {
        ++sequences;
        leftItems -= ((*occurrence)<<1)-1;
    }
    return sequences;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    
    cout << solve() << endl;
    
    return 0;
}