import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) {
        try {
            // 標準入力
            InputStreamReader isr = new InputStreamReader(System.in);
            BufferedReader br = new BufferedReader(isr);
            int n = Integer.parseInt(br.readLine());
            int a[] = new int[n];
            for (int i = 0; i < n; i++) {
                a[i] = Integer.parseInt(br.readLine());
            }
            int now = a[0];
            int count = 1;
            boolean flag = false;
            while (count < n) {
                if (now == 2) {
                    System.out.println(count);
                    flag = true;
                    break;
                }
                now = a[now - 1];
                count++;
            }
            if (!flag) {
                System.out.println(-1);
            }
        } catch (IOException e) {
            e.printStackTrace();
           }
    }
}
/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