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#include<bits/stdc++.h>

#define FOR(i,s,e) for(int i=(s); i<=(e); i++)
#define FORD(i,s,e) for(int i=(s); i>=(e); i--)
#define ALL(k) (k).begin(), (k).end()
#define e1 first
#define e2 second
#define mp make_pair
 
using namespace std;
using LL=long long;
using LD=long double;
using PII=pair<int,int>;

const int MAXN = 500111;

int counts[MAXN];

int main(){
    int n; scanf("%d", &n);
    FOR(i,1,n){
        int a; scanf("%d",&a);
        counts[a]++;
    }
    vector<PII> count_pairs;
    FOR(i,1,n){
        if (counts[i] > 0){
            count_pairs.push_back(mp(counts[i], i));
        }
    }
    sort(ALL(count_pairs));
    reverse(ALL(count_pairs));

    int lptr = 0, rptr = count_pairs.size() - 1;
    int minimum_subsequences = 0;

    while (lptr < rptr) {
        int quantity = count_pairs[lptr].e1 - 1;
        count_pairs[lptr].e1 = 0;
        minimum_subsequences += 1;
        while (rptr > lptr && quantity > 0) {
            int to_remove = min(quantity, count_pairs[rptr].e1);
            // printf("L %d R %d values %d %d, to_remove %d\n", lptr, rptr, count_pairs[lptr].e1, count_pairs[rptr].e1, to_remove);
            quantity -= to_remove;
            count_pairs[rptr].e1 -= to_remove;
            if (count_pairs[rptr].e1 == 0){
                rptr--;
            }
        }
        lptr++;
    }
    // printf("Fin: L %d R %d count %d\n", lptr, rptr, count_pairs[lptr].e1);
    if (lptr == rptr && count_pairs[lptr].e1 > 0){
        minimum_subsequences++;
    }
    printf("%d\n", minimum_subsequences);

}