
import java.util.Scanner;

class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] a = new int[n];
        
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int sum = 0;
        int i = 0;
        do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1);
        System.out.println(sum);      
    }
} import java.util.Scanner; Scanner java.util class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] a = new int[n];
        
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int sum = 0;
        int i = 0;
        do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1);
        System.out.println(sum);      
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] a = new int[n];
        
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int sum = 0;
        int i = 0;
        do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1);
        System.out.println(sum);      
    } main {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] a = new int[n];
        
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int sum = 0;
        int i = 0;
        do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1);
        System.out.println(sum);      
    } 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]; a new int[n] n for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        } int i = 0; int i = 0; i 0 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 sum = 0; sum 0 int i = 0; i 0 do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1); i != 1 i 1 {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } i = a[i] i a[i] a i i = i - 1 i i - 1 i 1 sum++ sum if (sum == n) {
                sum = -1;
                break;
            } sum == n sum n {
                sum = -1;
                break;
            } sum = -1 sum -1 1 break; System.out.println(sum) System.out.println System.out System System.out sum String[] args args

import java.util.Scanner;

class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int[] a = new int[n];
        
        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        int sum = 0;
        int i = 0;
        do {
            i = a[i];
            i = i - 1;
            sum++; 
            if (sum == n) {
                sum = -1;
                break;
            }
        } while (i != 1);
        System.out.println(sum);      
    }
}
