//查找兄弟单词

import java.util.*;

//查找兄弟单词
public class Main_222 {

    private static boolean isBrother(String str1, String str2){
        char[] chars1 = str1.toCharArray();
        char[] chars2 = str2.toCharArray();
        Arrays.sort(chars1);
        Arrays.sort(chars2);
        return new String(chars1).equals(new String(chars2)) && !str1.equals(str2);
    }

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        while(input.hasNextLine()){
            String line = input.nextLine();
            String[] words = line.split(" ");

            String item = words[words.length - 2];
            List<String> list = new ArrayList<>();
            for (int i = 1; i < words.length - 2; i++) {
                if(isBrother(words[i], item)){
                    list.add(words[i]);
                }
            }

            list.sort(String::compareTo);
            System.out.println(list.size());
            int index = Integer.parseInt(words[words.length - 1]);
            if(!list.isEmpty() && index <= list.size()){
                System.out.println(list.get(index - 1));
            }
        }
    }
}