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 ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		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 = sc.nextInt();
		int[] a = new int[N];
		for(int i = 0;i < N;++i)
			a[i] = sc.nextInt()-1;
		sc.close();
		
		int ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		else
			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];
		for(int i = 0;i < N;++i)
			a[i] = sc.nextInt()-1;
		sc.close();
		
		int ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		else
			System.out.println("-1");
	} 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 ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		else
			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]; 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] a i sc.nextInt()-1 sc.nextInt() sc.nextInt sc 1 sc.close() sc.close sc int ans = 0; ans 0 int current = 0; current 0 while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		} ans < N ans N {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		} ans++ ans if(a[current] == 1)
				break;
			else
				current = a[current]; a[current] == 1 a[current] a current 1 break; current = a[current] current a[current] a current if(ans < N)
			System.out.println(ans);
		else
			System.out.println("-1"); ans < N ans N System.out.println(ans) System.out.println System.out System System.out ans 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];
		for(int i = 0;i < N;++i)
			a[i] = sc.nextInt()-1;
		sc.close();
		
		int ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		else
			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];
		for(int i = 0;i < N;++i)
			a[i] = sc.nextInt()-1;
		sc.close();
		
		int ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		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 = sc.nextInt();
		int[] a = new int[N];
		for(int i = 0;i < N;++i)
			a[i] = sc.nextInt()-1;
		sc.close();
		
		int ans = 0;
		int current = 0;
		while(ans < N) {
			ans++;
			if(a[current] == 1)
				break;
			else
				current = a[current];
		}
		if(ans < N)
			System.out.println(ans);
		else
			System.out.println("-1");
	}
}
