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 b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			} 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 b = a[0]; b a[0] a 0 int res = 1; res 1 for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			} int i=0; int i=0; i 0 i<=n i n i++ i++ i {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			} {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			} if(b==2) {
					System.out.println(res);
					return;
				} b==2 b 2 {
					System.out.println(res);
					return;
				} System.out.println(res) System.out.println System.out System System.out res return; b =a[b-1] b a[b-1] a b-1 b 1 res++ res 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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			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();
			}
			
			int b = a[0];
			int res = 1;
			
			for(int i=0;i<=n;i++) {
				if(b==2) {
					System.out.println(res);
					return;
				}
				
				b =a[b-1];
				res++;
			}
			
			System.out.println("-1");
			
		}

	}