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];

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

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(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[] a = new int[N + 1];

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

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    }

  }

} 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 + 1; i++) {
      a[i] = sc.nextInt();
    }

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    }

  } main {

    Scanner sc = new Scanner(System.in);

    int N = sc.nextInt();
    int[] a = new int[N + 1];

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

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    }

  } 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 + 1; i++) {
      a[i] = sc.nextInt();
    } int i = 1; int i = 1; i 1 i < N + 1 i N + 1 N 1 i++ i++ i {
      a[i] = sc.nextInt();
    } {
      a[i] = sc.nextInt();
    } a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc sc.close() sc.close sc int count = 0; count 0 boolean valid = true; valid true int current = 1; current 1 while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    } valid {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    } count++ count current = a[current] current a[current] a current if (current == 2) {
        valid = false;
      } current == 2 current 2 {
        valid = false;
      } valid = false valid false if (count == N) {
        count = 0;
        valid = false;
      } count == N count N {
        count = 0;
        valid = false;
      } count = 0 count 0 valid = false valid false if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    } count == 0 count 0 {
      System.out.println(-1);
    } System.out.println(-1) System.out.println System.out System System.out -1 1 {
      System.out.println(count);
    } System.out.println(count) System.out.println System.out System System.out count 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 + 1; i++) {
      a[i] = sc.nextInt();
    }

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    }

  }

} 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 + 1; i++) {
      a[i] = sc.nextInt();
    }

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(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[] a = new int[N + 1];

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

    sc.close();

    int count = 0;

    boolean valid = true;
    int current = 1;

    while (valid) {

      count++;
      
      current = a[current];

      if (current == 2) {
        valid = false;
      }

      if (count == N) {
        count = 0;
        valid = false;
      }

    }

    if (count == 0) {
      System.out.println(-1);
    } else {
      System.out.println(count);
    }

  }

}