/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int arr[]=new int[n+1];
		for(int i=1;i<=n;i++) arr[i]=sc.nextInt();
		Map<Integer,Integer>mp=new HashMap<>();
		int count=0;
		for(int i=1;i<=n;i++){
			int temp=arr[arr[arr[i]]];
			if(mp.containsKey(temp)){
				count=count+mp.get(temp);
			}
			mp.put(temp,mp.getOrDefault(temp,0)+1);
		}
		System.out.println(count);
	}
}