#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;

int main(){


  int n,ans; cin >> n;ans = 0;
  vector<int> v(n);
  for (int i = 0; i < n; i++) {
    cin >> v[i];
  }
  sort(v.begin(),v.end());
  for (int i = 0; i < n - 2; i++) {
    if (v[i] != v[i + 1] && v[i + 1] != v[i + 2]) {
      ans++;
    }
  }
  if (v[0] != v[1]) {
    ans++;
  }
  if (v[n - 1] != v[n - 2]) {
    ans++;
  }
  cout << ans << "\n";
  return 0;
}