import java.util.Arrays;
import java.util.Scanner;

public class Problem1FilterArray {

    public static void main(String[] args) {

        Scanner scann = new Scanner(System.in);
        String[] input = scann.nextLine().split("\\s+");

        Arrays.stream(input)
                .filter(p -> p.length() > 3)
                .forEach(p -> System.out.print(p + " "));
    }
}