import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = scanner.nextInt();
		int[] a = new int[n];
		for(int i=0;i<n;i++){
			a[i] = scanner.nextInt() - 1;
		}
		int pos = 0;
		for(int i=0;i<n;i++){
			pos = a[pos];
			if(pos == 1){
				System.out.println(i+1);
				return;
			}
		}
		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