import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner sc = new Scanner(System.in);
        
        int n = sc.nextInt();
        int[] rs = new int[n-1];
        for(int i = 0 ; i < n - 1 ; i++){
            rs[i] = sc.nextInt();
        }
        
        int now = rs[0];
        int ans = 1;
        while(now != n){
            now = rs[now-1];
            ans++;
        }
        
        System.out.println(ans);
    }
}