import java.util.Scanner;


public class Luxor {

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