import java.io.*;
import java.util.*;
public class Main{
    public static void main(String[] args) throws IOException{
        MyReader r = new MyReader();    
        int N = r.i();
        int[] a = r.ii(N);
        for(int i = 1, count = 0; count < N;){
            i = a[i-1];
            count++;
            if(i == 2){
                println(count);
                return;
            } 
        }
        println(-1);
    }

    static void print(Object o){
        System.out.print(o.toString());
    }

    static void println(Object o){
        System.out.println(o.toString());
    }

    static int Int(String s){
        return Integer.parseInt(s);
    }

    static long Long(String s){
        return Long.parseLong(s);
    }
    static class MyReader extends BufferedReader{
        MyReader(){
            super(new InputStreamReader(System.in));
        }

        String s() throws IOException{
            return readLine();
        }

        String[] ss() throws IOException{
            return s().split(" ");
        }

        int i() throws IOException{
            return Int(s());
        }

        int[] ii() throws IOException{
            String[] ss = ss();
            int size = ss.length;
            int[] ii = new int[size];
            for(int j = 0; j < size; j++) ii[j] = Int(ss[j]);
            return ii;
        }

        long l() throws IOException{
            return Long(s());
        }

        long[] ll() throws IOException{
            String[] ss = ss();
            int size = ss.length;
            long[] ll = new long[size];
            for(int j = 0; j < size; j++) ll[j] = Long(ss[j]);            
            return ll;
        }

        int[] ii(int N) throws IOException{
            int[] ii = new int[N];
            for(int i = 0; i < N; i++) ii[i] = i();
            return ii;
        }

    }
}
/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