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+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    }
} import java.util.Scanner; Scanner 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+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int[] a = new int[N+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    } main {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int[] a = new int[N+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc int[] a = new int[N+1]; a new int[N+1] N+1 N 1 for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        } int i = 1; int i = 1; i 1 i <= N i N i++ i++ i {
            a[i] = sc.nextInt();
        } {
            a[i] = sc.nextInt();
        } a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc int count = 1; count 1 int x = a[1]; x a[1] a 1 for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        } int i = 1; int i = 1; i 1 i <= N i N i++ i++ i {
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        } {
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        } if(x == 2){
                System.out.println(count);
                return;
            } x == 2 x 2 {
                System.out.println(count);
                return;
            } System.out.println(count) System.out.println System.out System System.out count return; count++ count x = a[x] x a[x] a x System.out.println(-1) System.out.println System.out System System.out -1 1 String[] args args public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int[] a = new int[N+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    }
} public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int[] a = new int[N+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    }
} Main
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+1];
        for(int i = 1;i <= N;i++){
            a[i] = sc.nextInt();
        }
        int count = 1;
        int x = a[1];
        for(int i = 1;i <= N;i++){
            if(x == 2){
                System.out.println(count);
                return;
            }
            count++;
            x = a[x];
        }
        System.out.println(-1);
    }
}
