using System;
using System.Collections.Generic;
using System.Text;

class Program
{
    static List<string> variations = new List<string>();
    static int combLength;
    static void Main()
    {
        combLength = int.Parse(Console.ReadLine());
        string[] symbols = Console.ReadLine().Split(' ');
        char X = symbols[0][0];
        char Y = symbols[1][0];

        GenerateVariations("", X, Y);

        variations.Sort((x, y) => CustomSort(x, y));

        StringBuilder sb = new StringBuilder();
        foreach (var variation in variations)
        {
            sb.AppendLine(variation);
        }
        Console.WriteLine(sb.ToString());
    }

    private static int CustomSort(string x, string y)
    {
        for (int i = 0; i < x.Length; i++)
        {
            if (x[i] != y[i])
            {
                return x[i].CompareTo(y[i]);
            }
        }
        return x.CompareTo(y);
    }

    static void GenerateVariations(string current, char X, char Y)
    {
        if (current.Length == combLength)
        {
            variations.Add(current);
            return;
        }
        GenerateVariations(current + X, X, Y);
        GenerateVariations(current + Y, X, Y);
    }

}