#include <bits/stdc++.h>

using namespace std;

int main(){
        std::ios::sync_with_stdio(false);
	int n;
        
	while(cin >> n){
            vector<int> arr(n);
            vector<char> looped(n,false);
            for (int i = 0; i < n; i++) {
                cin >> arr[i];
                arr[i]--;
            }
            int ans = 0;
            for(int i=0;i<n;i++){
                if(!looped[i]){
                    looped[i] = true;
                    int start = i;
                    int k = arr[i];
                    int len = 0;
                    while(k != start){
                        looped[k] = true;
                        k = arr[k];
                        len++;
                    }
                    ans += len;
                }
            }
            cout << ans << endl;
	}
}