#include <bits/stdc++.h>


using namespace std;


typedef long long int ll;
typedef long double ld;

typedef pair<ll, ll> pi;
typedef pair<ld,ld> pd;

typedef vector<ll> vi;
typedef vector<ld> vd;
typedef vector<pi> vpi;

#define repab(i, a, b) for (ll i = (a); i < (b); i++)
#define repabs(i, a, b,s) for (ll i = (a); i < (b); i+=(s))
#define rep(i, a) for (ll i = 0; i < (a); i++)
#define rrepab(i,a,b) for (ll i = (b)-1; i >= (a); i--)
#define rrepabs(i,a,b,s) for (ll i = (b)-1; i >= (a); i-=(s))
#define rrep(i,a) for (ll i = (a)-1; i >= 0; i--)
#define iter(a, x) for (auto& a : x)
#define repeat(i, begin, end) for (__typeof(end) i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
#define GET5(a, b, c, d, e, ...) e
#define F_ORC(...) GET5(__VA_ARGS__, repabs, repab, rep)
#define F_ORRC(...) GET5(__VA_ARGS__, rrepabs, rrepab, rrep)
#define FOR(...) F_ORC(__VA_ARGS__)(__VA_ARGS__)
#define FORR(...) F_ORRC(__VA_ARGS__)(__VA_ARGS__)
#define v(a) vector<array<ll,a>>
#define minheap(a) priority_queue<array<ll,a>,vector<array<ll,a>>,greater<array<ll,a>> >
#define mat(n,m) vector<vi> matrix(vi(m),n)


#define rloop(n) int n;re(n);rep(i,n)
#define array(n) array<ll,n>
#define rea(arr,n) int n;re(n);vi arr(n);re(arr);

#define mk make_pair
#define pb push_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound

#define sz(x) (int)x.size()
#define beg(x) x.begin()
#define en(x) x.end()
#define all(x) beg(x), en(x)
#define resz resize


template<class T> void ckmin(T &a, T b) { a = min(a, b); }
template<class T> void ckmax(T &a, T b) { a = max(a, b); }

namespace io {
     #define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss);cerr<< "line: "<<__LINE__ <<" "; err(_it, args); cerr<<endl;}

    void err(istream_iterator<string> it) {}
    
    
   
    // TYPE ID (StackOverflow)
    template<class T> struct like_array : is_array<T>{};
    template<class T, size_t N> struct like_array<array<T,N>> : true_type{};
    template<class T> struct like_array<vector<T>> : true_type{};
    template<class T> bool is_like_array(const T& a) { return like_array<T>::value; }
    
    
    // INPUT 
    
    template<class T> void re(T& x) { cin >> x; }
    template<class Arg, class... Args> void re(Arg& first, Args&... rest);
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    
    template<class T1, class T2> void re(pair<T1,T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, size_t SZ> void re(array<T,SZ>& a);
    
    template<class Arg, class... Args> void re(Arg& first, Args&... rest) { re(first); re(rest...); }
    template<class T1, class T2> void re(pair<T1,T2>& p) { re(p.fi,p.se); }
    template<class T> void re(vector<T>& a) { rep(i,sz(a)) re(a[i]); }
    template<class T, size_t SZ> void re(array<T,SZ>& a) { rep(i,SZ) re(a[i]); }
    template<class T, size_t SZ> ostream& operator<<(ostream& os, const array<T,SZ>& a);
    template<class T> ostream& operator<<(ostream& os, const vector<T>& a);
    template<class T> ostream& operator<<(ostream& os, const set<T>& a) ;
    template<class T> ostream& operator<<(ostream& os, const multiset<T>& a) ;
    
    template<class T1, class T2> ostream& operator<<(ostream& os, const map<T1,T2>& a) ;
    // OUTPUT 
    
    template<class T1, class T2> ostream& operator<<(ostream& os, const pair<T1,T2>& a) {
        os << '{' << a.fi << ", " << a.se << '}'; return os;
    }
    template<class T> ostream& printArray(ostream& os, const T& a, int SZ) {
        os << '{';
        rep(i,SZ) {
            if (i) {
                os << ", ";
                if (is_like_array(a[i])) os << " ";
            }
            os << a[i];
        }
        os << '}';
        return os;
    }
    template<class T, size_t SZ> ostream& operator<<(ostream& os, const array<T,SZ>& a) {
        return printArray(os,a,SZ);
    }
    template<class T> ostream& operator<<(ostream& os, const vector<T>& a) {
        return printArray(os,a,sz(a));
    }
    template<class T> ostream& operator<<(ostream& os, const set<T>& a) {
        os << vector<T>(all(a)); return os;
    }
    template<class T> ostream& operator<<(ostream& os, const multiset<T>& a) {
        os << vector<T>(all(a)); return os;
    }
    template<class T1, class T2> ostream& operator<<(ostream& os, const map<T1,T2>& a) {
        os << vector<pair<T1,T2>>(all(a)); return os;
    }
    
    template<class T> void pr(const T& x) { cout << x << '\n'; }
    template<class Arg, class... Args> void pr(const Arg& first, const Args&... rest) { 
        cout << first << ' '; pr(rest...); 
    }
    template<typename T, typename... Args>
    void err(istream_iterator<string> it, T a, Args... args) {
        cerr << *it << " = " << a<<" " ;
        err(++it, args...);
    }
    template<typename T>
    void pa(vector<T> &a,bool psize=true){
        if(psize) cout<<a.size()<<"\n";
        iter(x,a) cout<<x<<" ";
        cout<<"\n";
    }
}
using namespace io;

const int MOD = 1000000007;
//const int MOD = 998244353;
const ll INF = 1e18;
const int MX = 2e5+1;

#define yes cout<<"YES\n"
#define no cout<<"NO\n"

void solve(){
   rea(a,n);
   int ans=0;
   vector<bool> vis(n,false);
   rep(i,n){
    if(vis[i]) continue;
    int p=i;
    int c=0;
    do{
        vis[p]=true;
        p=a[p]-1;
        c++;
    }while(p!=i);
    ////error(p,i,c);
    ans+=c-1;
   }
   cout<<ans<<"\n";
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    //rloop(t){
        solve();
    //}
    return 0;
}