import 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];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    System.out.println("-1");
  }

} 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[] a = new int[n+1];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    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];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    System.out.println("-1");
  } main {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] a = new int[n+1];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    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 int k = 1; k 1 int count = 0; count 0 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 for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    } int i = 1; int i = 1; i 1 i <= n i n i++ i++ i {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    } {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    } k = a[k] k a[k] a k count++ count if (k == 2) {
        System.out.println(count);
        return;
      } k == 2 k 2 {
        System.out.println(count);
        return;
      } System.out.println(count) System.out.println System.out System System.out count return; System.out.println("-1") System.out.println System.out System System.out "-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];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    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];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    System.out.println("-1");
  }

} Main
import 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];
    int k = 1;
    int count = 0;

    for (int i = 1; i <= n; i++) {
      a[i] = sc.nextInt();
    }

    for (int i = 1; i <= n; i++) {
      k = a[k];
      count++;
      if (k == 2) {
        System.out.println(count);
        return;
      }
    }
    System.out.println("-1");
  }

}
