import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Searcher {
  public static void main(String[] args) {
    String[] as = {"A", "B", "C", "D", "E"};
    List<String> ls = new ArrayList<String>();
    ls.addAll(Arrays.asList(as));
    System.out.println(ls);
    Scanner in = null;
    try {
      in = new Scanner(System.in);
    }
    catch (Exception e) {
    }
    List<String> qs = new ArrayList<String>();
    while (in.hasNextLine())
      qs.add(Pattern.quote(in.nextLine().trim()));
    StringBuilder sb = new StringBuilder();
    sb.append("(");
    Iterator<String> it = qs.iterator();
    while (it.hasNext()) {
      sb.append(it.next());
      if (it.hasNext()) sb.append("|");
    }
    sb.append(")");
    Pattern query = Pattern.compile(sb.toString());
    int find = 0;
    for (String s: ls) {
      Matcher m = query.matcher(s);
      if(m.find()) {
        find++;
        System.out.println(s);
      }
    }
    System.out.println((double)find / ls.size());
  }
}