import java.util.*;
public class Main{
    public static void main(String[]args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] a = new int[n];
        int cnt = 0;
        int s = 1;
        for(int i=0; i<n; i++){
            a[i] = sc.nextInt();
        }
        
        for(int i=0; i<a.length; i++){
            s = a[s-1];
            cnt++;
            if(s == 2){
                System.out.println(cnt);
                return;
            }
        }
        System.out.println("-1");
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz