#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); i++)
typedef long long ll;
typedef vector<ll> vll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<vector<ll>> vvll;
const ll inf = 1e16;
const ll md = 1000000007;

int main() {
  int n;
  cin >> n;
  vi a(n);
  rep(i, n) cin >> a[i];
  int ans = 0;
  map<int, int> cnt;
  rep(i, n) cnt[a[i]]++;
  for (pair<int, int> p : cnt)
    if (p.second == 1) ans++;
  cout << ans << endl;
  return 0;
}