import java.util.Arrays;
import java.util.Scanner;

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 count=0;
        int r=1;
        boolean aaaa=false;

        for(int i=0;i<n;i++){
            a[i]=sc.nextInt();
        }

        while(true){
            r=a[r-1];
            count++;
            if(r==2){
                aaaa=true;
                break;
            }
            if(count>n){
                break;
            }
        }

        if(aaaa){
            System.out.println(count);
        }else{
            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