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import java.util.*;

public class mis {

    private static int n;
    private static int m;
    private static int d;

    private static final Set<Set<Vertex>> maxCliques = new HashSet<>();


    public static void main(String[] args) {
        final Scanner sc = new Scanner(System.in);

        n = sc.nextInt();
        final Map<Integer, Vertex> vertices = new HashMap<>();
        for (int i = 1; i <= n; ++i) {
            vertices.put(i, new Vertex(i));
        }

        m = sc.nextInt();
        d = sc.nextInt();

        for (int i = 0; i < m; ++i) {
            int a = sc.nextInt();
            int b = sc.nextInt();
            addEdge(vertices, a, b);
        }

        BronKerbosch(new HashSet<>(), new HashSet<>(vertices.values()), new HashSet<>());

        if (maxCliques.isEmpty()) {
            System.out.println("NIE");
            return;
        }
        List<Set<Vertex>> merged = mergeCliques();

        Set<Vertex> maxSet = new HashSet<>();
        for (Set<Vertex> s : merged) {
            if (s.size() > maxSet.size()) {
                maxSet = s;
            }
        }
        List<Integer> ids = new ArrayList<>();
        for (Vertex v : maxSet) {
            ids.add(v.id);
        }
        Collections.sort(ids);

        System.out.println(ids.size());
        for (Integer i : ids) {
            System.out.print(i + " ");
        }
        System.out.println();
    }

    private static List<Set<Vertex>> mergeCliques() {
        boolean change = false;
        List<Set<Vertex>> current = new ArrayList<>(maxCliques);

        do {
            change = false;
            List<Set<Vertex>> newSet = new ArrayList<>();

            for (int i = 0; i < current.size(); ++i) {
                Set<Vertex> s1 = current.get(i);
                if (s1.isEmpty()) {
                    continue;
                }
                for (int j = i + 1; j < current.size(); ++j) {
                    Set<Vertex> s2 = current.get(j);
                    if (s2.isEmpty()) {
                        continue;
                    }
                    if (!intersect(s1, s2).isEmpty()) {
                        boolean isChange = s1.addAll(s2);
                        s2.clear();
                        change = change || isChange;
                    }
                }
                newSet.add(s1);
            }
            current = newSet;
        } while (change);

        //for (Set<Vertex> sss : current) {
        //    System.out.println(sss);
        //}
        return current;
    }

    private static void addEdge(Map<Integer, Vertex> vertices, int i, int j) {
        final Vertex v = vertices.get(i);
        final Vertex u = vertices.get(j);
        v.adj.add(u);
        u.adj.add(v);
    }

    private static void BronKerbosch(Set<Vertex> R, Set<Vertex> P, Set<Vertex> X) {
        //System.out.println(R + " | " + P + " | " + X);
        if (P.isEmpty() && X.isEmpty()) {
            if (R.size() > d) {
                //System.out.println("LOCAL MAX: " + R);
                maxCliques.add(new HashSet<>(R));
            }
        }

        final Set<Vertex> PP = new HashSet<>(P);
        for (Vertex v : P) {
            BronKerbosch(addSingle(R, v), intersect(P, v.adj), intersect(X, v.adj));
            R.remove(v);
            PP.remove(v);
            X.add(v);
        }
    }

    private static Set<Vertex> addSingle(Set<Vertex> set, Vertex vertex) {
        set.add(vertex);
        return set;
    }

    private static Set<Vertex> intersect(Set<Vertex> set1, Set<Vertex> set2) {
        final Set<Vertex> result;
        if (set1.size() > set2.size()) {
            result = new HashSet<>(set2);
            result.retainAll(set1);
        } else {
            result = new HashSet<>(set1);
            result.retainAll(set2);
        }
        return result;
    }

    private static class Vertex {
        private int id;
        private Set<Vertex> adj;

        public Vertex(int id) {
            this.id = id;
            this.adj = new HashSet<>();
        }

        @Override
        public String toString() {
            return "{" + id + '}';
        }
    }
}