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#include <bits/stdc++.h>

using namespace std;

int n;

vector<int> inverse(const vector<int> &v) {
  vector<int> res(n, 0);
  for (int i = 0; i < n; ++i)
    ++res[v[i]];
  return res;
}

int partition(vector<int> &cnt) {
  int i = 0, j = n - 1;
  int parts = 0;
  while (i <= j) {
    ++parts;
    int sz = cnt[j] - 1;
    while (i < j && cnt[i] <= sz)
      sz -= cnt[i++];

    cnt[i] -= sz;
    cnt[j--] = 0;
  }

  return parts;
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

  cin >> n;
  vector<int> v(n);
  for (int &i : v) {
    cin >> i;
    --i;
  }

  vector<int> cnt = inverse(v);
  sort(cnt.begin(), cnt.end());

  cout << partition(cnt) << '\n';
}