import java.util.Comparator;
import java.util.HashSet;
import java.util.PriorityQueue;
import java.util.Set;

public class NewClass {

    public static void main (String ... args) {
        PriorityQueue<Set<Integer>> queue = new PriorityQueue<Set<Integer>>(5, new Comparator<Set<Integer>>() {

            public int compare(Set<Integer> o1, Set<Integer> o2) {
                return o1.size() > o2.size() ? 1 : -1;
            }

        });

        for (int i = 0; i < 5; i++)
            queue.add(new HashSet<Integer>());

        for (int i = 0; i < 1000; i++) {
            Set<Integer> si = queue.poll();
            si.add((int) (Math.random() * 100));
            queue.add(si);
        }

        for (Set<Integer> s : queue) {
            for (int i : s)
                System.out.print(i + ", ");
            System.out.println();
        }
    }


}