#include <bits/stdc++.h>

#define rep(i, ss, ee) for (int i = ss; i < ee; ++i)
using namespace std;

int N;
map<int, int> m;

void input() {
  cin >> N;
  int x;
  rep(i, 0, N) {
    cin >> x;
    m[x]++;
  }
}

void solve() {
  int ans = 0;
  for (auto x : m)
    if (x.second == 1) ans++;
  cout << ans << endl;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  input();
  solve();
  getchar();
}