import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int[] button = new int[N];
		for(int i=0; i<N; i++) {
			button[i] = sc.nextInt();
		}

		int p = 0;
		for (int i = 0; i < N; i++ ) {
			int num = button[p];
			if(num == 2) {
				System.out.println(i+1);
				return;
			}
			p = num-1;
		}
		System.out.println(-1);
	}
}

/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