#include <bits/stdc++.h>

using namespace std;

typedef long long int ll;
typedef double ld;

typedef pair<ll, ll> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;

#define PB push_back
#define FOR(prom, a, b) for ( ll prom = (a); prom < (ll)(b); ++prom )
#define F(a) FOR(i,0,a)
#define FF(a) FOR(j,0,a)

#define EPS (1e-10)

int main () {
	ios::sync_with_stdio(false);	
	ll N;
	while ( cin >> N ) {
		ll COUNT = 0;
		vi ROOMS( N );
		F(N) { cin >> ROOMS[ i ]; ROOMS[ i ] -= 1; }
		
		F(N) {
			while ( ROOMS[ i ] != i ) {
				COUNT += 1;
				swap( ROOMS[ i ], ROOMS[ ROOMS[ i ] ] );
			}			
		}
		
		cout << COUNT << endl;
	}
	return 0;
}