import java.util.*;

public class Main{
    void solve(){
        Scanner scan = new Scanner(System.in);
        int n = scan.nextInt();
        int[] a = new int[n];
        for(int i = 0; i < n; i++) a[i] = scan.nextInt() - 1;
        int out = 0;
        for(int i = 0; out < n; i = a[i]){
            if(i == 1){
                System.out.println(out);
                return;
            }
            out++;
        }
        System.out.println(-1);
        scan.close();
    }

    public static void main(String[] args){
        new Main().solve();
    }
}

/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