import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	}
} import java.util.Scanner; Scanner java.util public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	} main {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = Integer.valueOf(sc.nextInt()); N Integer.valueOf(sc.nextInt()) Integer.valueOf Integer sc.nextInt() sc.nextInt sc int a[] = new int[N]; a new int[N] N int i; i for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		} i=0; 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 judge=0; judge 0 i = 0 i 0 int count=0; count 0 while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		} judge != 2 judge 2 {
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		} judge = a[i] judge a[i] a i count++ count i = judge-1 i judge-1 judge 1 if(count > N) break; count > N count N break; if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		} count<N count N {
			System.out.println(count);
		} System.out.println(count) System.out.println System.out System System.out count {
			System.out.println(-1);
		} System.out.println(-1) System.out.println System.out System System.out -1 1 String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	}
} Main
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = Integer.valueOf(sc.nextInt());
		int a[] = new int[N];
		int i;

		for(i=0; i<N; i++){
			a[i] = sc.nextInt();
		}

		int judge=0;
		i = 0;
		int count=0;
		while(judge != 2){
			judge = a[i];
			count++;
			i = judge-1;
			if(count > N) break;
		}
		if(count<N){
			System.out.println(count);
		}
		else{
			System.out.println(-1);
		}
	}
}