#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;

int n;
map<ll, int> mp;

int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    ll a; cin >> a;
    mp[a]++;
  }
  int ans = 0;
  for (auto p: mp) {
    if (p.second == 1) ans++;
  }
  cout << ans << endl;
  return 0;
}