import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();
		int[] num = new int[n];
		for (int i = 0; i < num.length; i++) {
			num[i] = scanner.nextInt();
		}
		boolean[] check = new boolean[n];
		int i = 0;
		int count = 0;
		while (!check[i]) {
			//System.out.println(i);
			count++;
			check[i] = true;
			i = num[i] - 1;
			if (i == 1) {
				System.out.println(count);
				System.exit(0);
			}
		}
		System.out.println("-1");
		scanner.close();
	}
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz