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

#define PB push_back
#define CL(A, I) (memset(A, I, sizeof(A)))
#define D(X) cout<<"  "<<#X": "<<X<<endl;
#define FOR(i, m, n) for(int i(m); i < n; i++)
#define F(n) FOR(i, 0, n)
#define FF(n) FOR(j, 0, n)
#define aa first
#define bb second

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

int x[223456], n;

int main() {
    while(scanf("%d", &n) == 1) {
        F(n) {
            scanf("%d", &x[i]);
            x[i]--;
        }
        int cnt = 0;
        F(n) {
            while (x[i] != i) swap(x[i], x[x[i]]), cnt++;
        }
        printf("%d\n", cnt);
    }
}