import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());
        int[] a = new int[n+1];
        for(int i=1; i<=n; i++) {
            a[i] = Integer.parseInt(sc.next());
        }
        int[] b = new int[n+1];
        b[0] = 1;
        int i= 1;
        int ans = -1;
        while(i <= n) {
            b[i] = a[b[i-1]];
            if(b[i] == 2) {
                ans = i;
                break;
            }
            i++;
        }
        
        System.out.println(ans);
    }

}

/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