import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Main {

	public static void main(String args[]) {
		FastScanner cin = new FastScanner();
		PrintWriter cout = new PrintWriter(System.out);
		solve(cin, cout);
		cout.flush();
	}

	private static void solve(FastScanner cin, PrintWriter cout) {
		int n = cin.nextInt();
		int[] a = new int[n];
		for (int i = 0; i < n; i++)
			a[i] = cin.nextInt() - 1;

		int ans = solve(n, a);
		cout.println(ans);
	}

	private static int solve(int n, int[] a) {
		int here = 0;
		int ans = 0;
		for (int i = 0; i < n; i++) {
			ans += 1;
			here = a[here];
			if (here == 1)
				return ans;
		}
		return -1;
	}

	/**
	 * How to read input in Java — tutorial <br />
	 * By Flatfoot<br />
	 * http://codeforces.com/blog/entry/7018
	 */
	static class FastScanner {
		private BufferedReader br;
		private StringTokenizer st;

		FastScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements())
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					throw new IllegalStateException(e);
				}
			return st.nextToken();
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				throw new IllegalStateException(e);
			}
			return str;
		}

		long nextLong() {
			return Long.parseLong(next());
		}
	}

}

/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