#include <bits/stdc++.h>
using namespace std;

#define FOR(i,a,b) for(auto i=a;i<b;++i)
#define F(a) FOR(i,0l,a)
#define FF(a) FOR(j,0l,a)
#define aa first
#define bb second
#define PB push_back
#define pb push_back
#define MOD ((int)1e9+7)
#define INF (1<<30)
#define LINF (1L<<61)
#define EPS (1e-10)
#define EQ(a,b) (fabs(a-b)<=(fabs(a+b)*EPS))
#ifdef DEBUG
#define DEB puts("DEB!")
#define DPRINT(X) printf("#X: %d\n",X)
#define dout cout
#else
#define DEB do{}while(0)
#define DPRINT(X) do{}while(0)
#define dout 0 && cout
#endif
using ll=long long;
using ull=unsigned long long;
using ld=double;
using vi=vector<int>;
using vvi=vector<vi>;
using pii=pair<int,int>;

int main(){
  ios::sync_with_stdio(false);cout.tie(0);cin.tie(0);
  while (1) {
    int n;
    cin >> n;
    if (!cin) break;
    vector<ll> a(n + 1);
    for (int i = 1; i <= n; ++ i) cin >> a[i];
    ll r = 0;
    vector<bool> v(n + 1, false);
    for (int i = 1; i <= n; ++ i) {
      if (v[i]) continue;
      int c = i;
      int cc = 1;
      if (c == a[i]) {
        v[i] = true;
        continue;
      }

      while (!v[c]) {
        cc ++;
        v[c] = true;
        c = a[c];
      }

      r += cc - 2;
      v[c] = true;

    }

    cout << r << endl;

  }
  return 0;
}