import java.util.*;
import java.math.RoundingMode;
import java.math.BigDecimal;
 
public class Main {
	
	
	 
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	}
} import java.util.*; util.* java import java.math.RoundingMode; RoundingMode java.math import java.math.BigDecimal; BigDecimal java.math public class Main {
	
	
	 
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	}
} Main public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	} main {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int a[] = new int[n]; a new int[n] n for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
        	a[i] = sc.nextInt();
        } {
        	a[i] = sc.nextInt();
        } a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc int count=0; count 0 int now = 1; now 1 while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        } now!=2&&count<=n+1 now!=2 now 2 count<=n+1 count n+1 n 1 {
        	now = a[now-1];
        	count++;
        } now = a[now-1] now a[now-1] a now-1 now 1 count++ count if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        } now != 2 now 2 {
            System.out.println(-1);
        } System.out.println(-1) System.out.println System.out System System.out -1 1 {
        	System.out.println(count);
        } System.out.println(count) System.out.println System.out System System.out count String[] args args public class Main {
	
	
	 
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	}
} public class Main {
	
	
	 
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	}
} Main
import java.util.*;
import java.math.RoundingMode;
import java.math.BigDecimal;
 
public class Main {
	
	
	 
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
        int a[] = new int[n];
        for(int i = 0; i < n; i++) {
        	a[i] = sc.nextInt();
        }
        int count=0;
        int now = 1;
        while(now!=2&&count<=n+1) {
        	now = a[now-1];
        	count++;
        }
        if(now != 2) {
            System.out.println(-1);
        }
        else {
        	System.out.println(count);
        }
	}
}