import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.StringTokenizer;

public class Main {




    public static void main(String[] args) throws IOException {


        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));


        while (true)
        {
            String tmp = in.readLine();
            if(tmp == null) break;

            int num = Integer.parseInt(tmp);

            ArrayList<Integer> numbers = new ArrayList<>();
            StringTokenizer stringTokenizer = new StringTokenizer(in.readLine());
            for (int i = 0; i < num; i++){
                numbers.add(Integer.parseInt(stringTokenizer.nextToken()));
            }

            int numberOfEpisodes = 0;

            for(int i = 0; i < numbers.size(); i++)
            {
                while (i+1 != numbers.get(i))
                {
                    Integer temporary = numbers.get(numbers.get(i)-1);
                    numbers.set(numbers.get(i)-1, numbers.get(i));
                    numbers.set(i, temporary);
                    numberOfEpisodes++;
                }
            }

            System.out.println(numberOfEpisodes);

        }



    }
}