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();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            System.out.println("-1");
        }else{
            System.out.println(count);
        }
    }
} 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();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            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];
        for(int i=0;i<N;i++){
            a[i]=sc.nextInt();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            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];
        for(int i=0;i<N;i++){
            a[i]=sc.nextInt();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            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]; 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 count=0; count 0 int b=0; b 0 boolean ans=false; ans false while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        } count++<=N count++ count N {
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        } b=a[b]-1 b a[b]-1 a[b] a b 1 if(b==1){
                 ans=true;
                 break;
             } b==1 b 1 {
                 ans=true;
                 break;
             } ans=true ans true break; if(ans==false){
            System.out.println("-1");
        }else{
            System.out.println(count);
        } ans==false ans false {
            System.out.println("-1");
        } System.out.println("-1") System.out.println System.out System System.out "-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];
        for(int i=0;i<N;i++){
            a[i]=sc.nextInt();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            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];
        for(int i=0;i<N;i++){
            a[i]=sc.nextInt();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            System.out.println("-1");
        }else{
            System.out.println(count);
        }
    }
} 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();
        }
        int count=0;
        int b=0;
        boolean ans=false;
        while(count++<=N){
             b=a[b]-1;
             if(b==1){
                 ans=true;
                 break;
             }
        }
        if(ans==false){
            System.out.println("-1");
        }else{
            System.out.println(count);
        }
    }
}
