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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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 sc.close() sc.close sc int[]color = new int[N + 1]; color new int[N + 1] N + 1 N 1 int k = a[0] - 1; k a[0] - 1 a[0] a 0 1 color[1] = 1 color[1] color 1 1 int cnt = 1; cnt 1 for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		} int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		} {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		} if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			} k == 1 k 1 {
				System.out.println(cnt);
				System.exit(0);
			} System.out.println(cnt) System.out.println System.out System System.out cnt System.exit(0) System.exit System 0 {
				cnt++;
				k = a[k] - 1;
			} cnt++ cnt k = a[k] - 1 k a[k] - 1 a[k] a k 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];
		for(int i = 0; i < N; i++) {
			a[i] = sc.nextInt();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		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();
		}
		sc.close();
		int[]color = new int[N + 1];
		int k = a[0] - 1;
		color[1] = 1;
		int cnt = 1;
		for(int i = 0; i < N; i++) {
			if(k == 1) {
				System.out.println(cnt);
				System.exit(0);
			}else {
				cnt++;
				k = a[k] - 1;
			}
		}
		System.out.println(-1);
	}
}