import java.util.*;
import java.util.regex.*;
import java.lang.*;
import java.io.*;

class Ideone {
	public static void main (String[] args) throws java.lang.Exception {
		String input = "w ww www wwww wwwww wwwwwww wwwwww aaa bbb zzzzzz cccc";
        Pattern pattern = Pattern.compile("\\b\\w{3,5}\\b");
        Matcher matcher = pattern.matcher(input);
        int count = 0;
        while (matcher.find()) {
            count++;
        }
        count -= count % 2;
        String result = String.join("", (CharSequence[]) pattern.split(input, count + 1));
        System.out.println(result);
	}
}