import java.util.*;
 
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
 
        long n = scanner.nextLong();
        int[] v = new int[(int) n + 1];
 
        for (int i = 1; i <= n; i++) {
            v[i] = scanner.nextInt();
        }
 
        Map<Integer, Long> mp = new HashMap<>();
        long ans = 0;
 
        for (int i = 1; i <= n; i++) {
            int key = v[v[v[i]]];
            mp.put(key, mp.getOrDefault(key, 0L) + 1);
            // ans = Math.max(ans, mp.get(key));
        }
 
        for (long x : mp.values()) {
            ans += (x * (x - 1)) / 2;
        }
 
        System.out.println(ans);
        scanner.close();
    }
}
 

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