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#include <algorithm>
#include <cstdio>
#include <cstring>
#include <vector>

const int NN = 500500;
int D[NN];
int N, c;
bool DEBUG = false;

std::vector<int> uses;

int main() {
  memset(D, 0, sizeof(int) * NN);
  scanf("%d", &N);
  for (int i = 0; i < N; ++i) {
    scanf("%d", &c);
    ++D[c];
  }
  for (int i = 1; i <= N; ++i) {
    if (DEBUG)
      printf("%d ", D[i]);
    if (D[i] > 0) {
      uses.push_back(D[i]);
    }
  }
  if (DEBUG)
    puts("X");
  sort(uses.begin(), uses.end());
  if (DEBUG) {
  for (const int &u : uses)
    printf("%d ", u);
  }

  if (DEBUG)
    puts("");
  if (DEBUG)
    puts("");

  int groups = 1;
  auto left = uses.begin();
  int leftValue = *left;

  for (auto right = --uses.end(); left != right; --right) {
    int pool = *right;
    if (DEBUG)
      printf("pool: %d\n", pool);
    while (leftValue < pool) {
      pool -= leftValue;
      ++left;
      if (left == right)
        break;

      leftValue = *left;
      if (DEBUG)
        puts("eaten");
    }
    leftValue -= (pool - 1);
    if (DEBUG)
      printf("leftValueLeft %d\n", leftValue);
    if (left == right)
        break;
    groups += 1;
  }

  printf("%d\n", groups);

  return 0;
}