import java.util.Arrays;
import java.util.Scanner;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
/**
 *
 * @author cteam037
 */
public class Monsters {

    int counter = 0;
    //int[] t;
    int[] c;
    int n = 0;

    void run() {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            n = sc.nextInt();
            //t = new int[n];
            c = new int[n];
            for (int i = 0; i < n; i++) {
                c[i] = sc.nextInt() - 1;
            }
            //inicialize();
            //System.out.println(n+" b");
            //9 8 10 5 3 2 4 7 6 1
            for (int index = 0; index < n; index++) {
                while (c[index] != index) {
                    //int where = get(index, index);
                    int where = c[index];
                    int here = c[index];
                    c[index] = c[where];
                    c[where] = here;
                    counter++;
                }

            }
            System.out.println(counter);
            counter = 0;
        }
    }

    /*int get(int ch, int what) {
        for (int i = ch; i < n; i++) {
            if (c[i] == what) {
                return i;
            }
        }
        System.out.println("chyba");
        return -7;
    }*/

 /*void inicialize() {
        //parent t[]
        /*t[0] = c[0];
        for (int i = 1; i < n; i++) {
            int now = c[i];
            if(t[i/2]>now){
                t[i]=now;
            }else{
                t[i+1]=now;
            }
        }*/
 /*for (int i = 0; i < n; i++) {
            t[i] = c[i];
        }
        Arrays.sort(t);
    }*/
    public static void main(String[] args) {
        new Monsters().run();
    }
}