using System;
using System.ComponentModel.DataAnnotations;
using System.Diagnostics.Tracing;
using System.Reflection;
using System.Reflection.Metadata;
using System.Runtime.ExceptionServices;

namespace ExercisesForSoftuni
{
    class Program
    {
        static void Main(string[] args)
        {
            int k = int.Parse(Console.ReadLine());//6
            int l = int.Parse(Console.ReadLine());//7
            int m = int.Parse(Console.ReadLine());//5
            int n = int.Parse(Console.ReadLine());//6

            for (int i = k; i <= 8; i++) // 6
            {
                if (i % 2 == 0)
                {
                    for (int j = 9; j >= l; j--) // 9
                    {
                        if (j % 2 == 1)
                        {
                            for (int o = m; o <= 8; o++) // 6
                            {
                                if (o % 2 == 0)
                                {
                                    for (int p = 9; p >= n; p--) // 7
                                    {
                                        if (p % 2 == 1)
                                        {
                                            if (i % 2 == 0 && j % 2 == 1 && o % 2 == 0 & p % 2 == 1)
                                            {
                                                if (i == o && j == p)
                                                {
                                                    Console.WriteLine($"Cannot change the same player.");
                                                }
                                                else
                                                {
                                                    Console.WriteLine($"{i}{j} - {o}{p}");
                                                }
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }

        }
    }
}