#include <iostream>

using namespace std;

int n, ans;
char c;
bool visited[200004];
int data[200004];

int main()
{
    ios::sync_with_stdio(false);
   while(cin >> n)
   {
        int res = 0;
        for(int i = 0; i <= 200000; i++) {
            visited[i] = false;
        }
        for(int i = 1; i <= n; i++) {
           cin >> data[i];
        }

        //alg
        for(int i = 1; i <= n; i++) {
           if (visited[i] == false) {
                //int first = i;
                int len = 1;
                visited[i] = true;
                int id = data[i];
                //cout << id;
                while(id != i){
                    len++;
                    visited[id] = true;
                    id = data[id];

                }
                res += len-1;
           }
        }
        cout << res << endl;
   }
    return 0;
}