package aud6zad8;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;

public class LuckySuitor {

    public static final int RIGHT = 1; // --->
    public static final int LEFT = -1; // <---

    public static int whoIsLucky(int n) {

        List<Integer> positions = new ArrayList<Integer>();

        for (int i = 1; i <= n; i++) {
            positions.add(i);
        }

        ListIterator<Integer> it = positions.listIterator();
        printList(positions);

        while (true) {

            int dir = RIGHT;
            int count = 0;

            while (it.hasNext() && dir == RIGHT) {
                it.next();
                count++;
                if (count == 3) {
                    count = 0;
                    it.remove();
                    printList(positions);
                }

                if (!it.hasNext()) {
                    it.previous();
                    dir = LEFT;
                    break;
                }
            }

            while (it.hasPrevious() && dir == LEFT) {
                count++;
                it.previous();
                if (count == 3) {
                    count = 0;
                    it.remove();
                    printList(positions);
                }

                if (!it.hasPrevious()) {
                    it.next();
                    dir = RIGHT;
                    break;
                }

            }

            if (positions.size() == 1) {
                break;
            }

        }

        return 0;
    }

    public static void printList(List<Integer> list) {
        Iterator<Integer> it = list.iterator();

        while (it.hasNext()) {
            System.out.print(it.next() + " ");
        }
        System.out.println();
    }

    public static void main(String[] args) {
        System.out.println("\n\n" + whoIsLucky(5));
    }

}