import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    } main {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int[] array = new int[n]; array new int[n] n for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
            array[i] = sc.nextInt();
        } {
            array[i] = sc.nextInt();
        } array[i] = sc.nextInt() array[i] array i sc.nextInt() sc.nextInt sc int point = 1; point 1 int count = 0; count 0 while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        } point != 2 && count < n point != 2 point 2 count < n count n {
            point = array[point-1];
            count++;
        } point = array[point-1] point array[point-1] array point-1 point 1 count++ count System.out.println(count==n?-1:count) System.out.println System.out System System.out count==n?-1:count count==n count n -1 1 count String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i=0; i<n; i++) {
            array[i] = sc.nextInt();
        }
        int point = 1;
        int count = 0;
        while (point != 2 && count < n) {
            point = array[point-1];
            count++;
        }
        System.out.println(count==n?-1:count);
    }
}