using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ahanem
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = Convert.ToInt32(Console.ReadLine());
            int[] v = Console.ReadLine().Split().Select(int.Parse).ToArray();
            List<int> l = new List<int>();
            int a = 0; int b = 0;
            for (int i = 0; i < n; i++)
            {
                l.Add(v[i]);
            }
            l.Sort();
            a = l[0]; b = l[n - 1];
            if (b - a == 0)
            {
                Console.WriteLine("-1");
            }
            else
            {
                Console.WriteLine(a + " " + b);
            }
            Console.ReadKey();
        }
    }
}