07. Append Arrays

import java.util.*;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String input = scanner.nextLine(); //"1 2 3 |4 5 6 |  7  8"
        List<String> list = Arrays.stream(input.split("\\|")).collect(Collectors.toList());
        Collections.reverse(list);
        //list.toString() ->
        // "[  7  8, 4 5 6 , 1 2 3 ]"
        // replace [ -> "  7  8, 4 5 6 , 1 2 3 ]"
        // replace ] -> "  7  8, 4 5 6 , 1 2 3 "
        // replace , -> "  7  8 4 5 6  1 2 3 "
        //trim() -> "7  8 4 5 6  1 2 3"
        //replace more than one interval -> "7 8 4 5 6 1 2 3"
        System.out.println(list.toString().replace("[", "")
                                            .replace("]", "")
                                            .replaceAll(",", "")
                                            .trim()
                                            .replaceAll("\\s+", " "));


    }

}