#include <iostream>
#include <vector>
#define MAX 300000
#define LL long long

using namespace std;

int main() {
    std::iostream::sync_with_stdio(false);
    LL N;
    vector<LL> perm(MAX);
    vector<LL> vis(MAX, 0);
    
    LL f = 1;
    while (cin >> N) {
        for (int i = 1; i <= N; ++i) {
            cin >> perm[i];
        }    
        
        LL swaps = 0;
        for (int i = 1; i <= N; ++i) {
            if (vis[i] == f) {
                continue;
            }
            vis[i] = f;
            LL next = perm[i];
            while (next != i) {
                ++swaps;
                vis[next] = f;
                next = perm[next];
            }
        }
        
        cout << swaps << endl;
        ++f;
    }
    return 0;
}