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];
        for(int i=0; i<n; i++) {
            a[i] = sc.nextInt()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    }
} 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];
        for(int i=0; i<n; i++) {
            a[i] = sc.nextInt()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    }
} 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()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    } 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()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    } 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()-1;
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
            a[i] = sc.nextInt()-1;
        } {
            a[i] = sc.nextInt()-1;
        } a[i] = sc.nextInt()-1 a[i] a i sc.nextInt()-1 sc.nextInt() sc.nextInt sc 1 sc.close() sc.close sc int cnt = 0; cnt 0 int tmp = 0; tmp 0 for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        } {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        } cnt++ cnt tmp = a[tmp] tmp a[tmp] a tmp if(tmp == 1) {
                break;
            } tmp == 1 tmp 1 {
                break;
            } break; if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        } cnt == n cnt n {
            System.out.println(-1);
        } System.out.println(-1) System.out.println System.out System System.out -1 1 {
            System.out.println(cnt);
        } System.out.println(cnt) System.out.println System.out System System.out cnt 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];
        for(int i=0; i<n; i++) {
            a[i] = sc.nextInt()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    }
} public 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()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    }
} 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];
        for(int i=0; i<n; i++) {
            a[i] = sc.nextInt()-1;
        }
        sc.close();

        int cnt = 0;
        int tmp = 0;
        for(int i=0; i<n; i++) {
            cnt++;
            tmp = a[tmp];
            if(tmp == 1) {
                break;
            }
        }
        if(cnt == n) {
            System.out.println(-1);
        } else {
            System.out.println(cnt);
        }
    }
}
