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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1]; a new int[N+1] N+1 N 1 for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		} int i = 1; int i = 1; i 1 i < N+1 i N+1 N 1 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 nextPosition = a[1]; nextPosition a[1] a 1 int count = 0; count 0 while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		} true {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		} count++ count if(count == N || nextPosition == 2) {
				break;
			} count == N || nextPosition == 2 count == N count N nextPosition == 2 nextPosition 2 {
				break;
			} break; nextPosition = a[nextPosition] nextPosition a[nextPosition] a nextPosition if(count == N) {
			System.out.println("-1");
		} else {
			System.out.println(count);
		} count == N count N {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			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+1];
		for(int i = 1; i < N+1; i++) {
			a[i] = sc.nextInt();
		}

		int nextPosition = a[1];
		int count = 0;
		while(true) {
			count++;
			if(count == N || nextPosition == 2) {
				break;
			}
			nextPosition = a[nextPosition];
		}
		if(count == N) {
			System.out.println("-1");
		} else {
			System.out.println(count);
		}
	}
}