import java.util.List;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Scanner;

public class Main
{
   public static void main(String[] args)
   {
   	  Scanner s = new Scanner(System.in);
   	  while (s.hasNextLine())
   	  {
	      List<String> array = Arrays.asList(s.nextLine().trim().split(" +"));
	      Collections.sort(array, new StrCompare());
	      System.out.println(array);
	      for (String str : array)
	      {
	         System.out.print(str);
	      }
	      System.out.println();
   	  }
   }
}

class StrCompare implements Comparator<String>
{
   @Override
   public int compare(String s1, String s2)
   {
      int i;
      int length = s1.length() + s2.length();
      for (i = 0; i < length; i++)
      {
         char c1 = get(s1, s2, i), c2 = get(s2, s1, i);
         if (c1 != c2)
         {
            return (c1 > c2 ? -1 : 1);
         }
      }
      return 0;
   }
   
   private char get(String s1, String s2, int index)
   {
      if (index < s1.length())
         return s1.charAt(index);
      else
         return s2.charAt(index - s1.length());
   }
}