import java.util.*;

import static com.sun.tools.sjavac.Util.union;

public class Graph {
    private List<Integer>[] nb;
    private int n;
    Graph (int n) {
        this.n=n;
        nb = new ArrayList[n];
        for (int i=0; i<n; i++)
            nb[i] = new ArrayList<>();
    }
    void addEdge (int a, int b) {
        nb[a].add(b);
        nb[b].add(a);
    }
    Set<Set<Integer>> sets;
    Set<Integer>[] ns;
    Set<Set<Integer>> complimentComponent () {
        sets = new HashSet<>();
        ns = new HashSet[n];
        for (int i=0; i<=n; i++) {
            Set<Integer> s = HashSet<Integer>.Singleton(i);
            sets.add(s);
            ns[i]=s;
        }
        for (int i=0; i<n; i++) process(i);
        return sets;
    }
    void process (int a) {
        Map<Set<Integer>, Integer> c = new HashMap<>();
        for (Set <Integer> s : sets) {
            c.put(s, 0);
        }
        for (int b : nb[a]) {
            c.put(ns[b], c.get(ns[b])+1);
        }
        for (Set<Integer> s : sets) {
            if (s != ns[a] && c.get(s) < s.size()) { // porównuje wskażniki
                union (ns[a], s);
            }
        }
    }
    void union (Set<Integer> s, Set<Integer> t) {
        if (s.size() < t.size()) {
            union (t, s); return;
        }
        s.addAll(t);
        for (int a : t) {
            ns[a] = s;
        }
        sets.remove(t);
    }
}



public class Main {
    public static void main (String[] argv) {

    }
}