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];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			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 = sc.nextInt();
		int a[] = new int[N];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			System.out.println(count);
		} 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];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			System.out.println(count);
		} else {
			System.out.println(-1);
		}
	} main {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int a[] = new int[N];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			System.out.println(count);
		} 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 boolean can = false; can false int nextId = 0; nextId 0 int count = 0; count 0 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 while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		} count != N count N {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		} nextId = a[nextId] - 1 nextId a[nextId] - 1 a[nextId] a nextId 1 count++ count if (nextId == 1) {
				can = true;
				break;
			} nextId == 1 nextId 1 {
				can = true;
				break;
			} can = true can true break; if (can) {
			System.out.println(count);
		} else {
			System.out.println(-1);
		} can {
			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 = sc.nextInt();
		int a[] = new int[N];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			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 = sc.nextInt();
		int a[] = new int[N];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			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 = sc.nextInt();
		int a[] = new int[N];
		boolean can = false;
		int nextId = 0;
		int count = 0;

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

		while (count != N) {
			nextId = a[nextId] - 1;
			count++;
			if (nextId == 1) {
				can = true;
				break;
			}
		}

		if (can) {
			System.out.println(count);
		} else {
			System.out.println(-1);
		}
	}
}
