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#include <map>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <vector>
#include <iostream>
#include <algorithm>

struct AllSetsIterator {
    AllSetsIterator(size_t n) : n(n), s(0) {}
    
    void advance() {
        while (!cur.empty() && cur.back() >= int(n - (s - cur.size() + 1)) ) {
            cur.pop_back();
        }
        if (cur.empty()) {
            ++s;
            if (done()) return;
            cur.push_back(0);
        } else {
            cur.back()++;
        }
        while (cur.size() < s) {
            cur.push_back(cur.back() + 1);
        }
    }

    bool done() {
        return s > n;
    }

    const std::vector<int> current() {
        return cur;
    }
private:
    const size_t n;
    std::vector<int> cur;
    size_t s;
};

void test() {
/*
    AllSetsIterator it(7);
    while (!it.done()) {
        for (const auto& s : it.current()) {
            std::clog << s << " ";
        }
        std::clog << std::endl;
        it.advance();
    }
*/

    int edges = 0;
    std::unordered_map<int, std::unordered_set<int>> g;
    for (int i=1; i<=200000; ++i) {
        for (int j=0;j<1000; ++j) {
            int r = rand();
            if (r % 107 == 0) {
                int node = r % 200001;
                if (i < node) {
                    g[i].insert(node);
                    ++edges;
                }
            }
        }
    }

    std::cout << 200000 << " " << edges << " d" << std::endl;
    for (const auto& d : g) {
        for (int i : d.second) {
            std::cout << d.first << " " << i << std::endl;
        }
    }
}

bool verify(
        const std::vector<std::vector<int>>& nb,
        const std::unordered_set<int>& choice,
        const int d,
        std::unordered_set<int> canVisit
) {
    if (canVisit.begin() == canVisit.end()) return false;
    int start = *canVisit.begin();

    std::vector<int> toVisit(1, start);

    while (!toVisit.empty()) {
        int cur = toVisit.back();
        toVisit.pop_back();
        canVisit.erase(cur);

        int connectsTo = 0;
        for (int neighbor : nb[cur]) {
            if (choice.count(neighbor) > 0) ++connectsTo;
            if (canVisit.count(neighbor) > 0) toVisit.push_back(neighbor);
        }
        if (connectsTo < d) return false;
    }
    return canVisit.empty();
}

int main() {
    //test(); return 0;
    size_t n,m,d;
    std::cin >> n >> m >> d;
    std::vector<std::vector<int>> nb(n+1);
    for (size_t i=0;i<m;++i) {
        int a,b;
        std::cin >> a >> b;
        nb[a].push_back(b);
        nb[b].push_back(a);
    }

    // sort by degree
    std::multimap<size_t,int> byDegree;
    for (size_t i=1; i<=n; ++i) {
        byDegree.insert(std::make_pair(nb[i].size(), i));
    }

    // order of nodes to work
    std::vector<int> ord;
    ord.reserve(n);
    // set of applicable nodes (deg(i) >= 1)
    std::unordered_set<int> mask;
    for (const auto& p : byDegree) {
        ord.push_back(p.second);
        if (p.first >= d) {
            mask.insert(p.second);
        }
    }
    int firstOk = -1;
    for (size_t i=0; i<n; ++i) {
        if (nb[ord[i]].size() >= d) {
            firstOk = i;
            break;
        }
    }
    size_t possible = (firstOk < 0) ? 0 : (n - firstOk);
    if (possible < d) {
        std::cout << "NIE" << std::endl;
        return 0;
    }

    // verify each set?
    AllSetsIterator it (possible);
    while (!it.done()) {
        auto usedMask = mask;
        for (int i : it.current()) {
            usedMask.erase(ord[firstOk + i]);
        }
        // sets smaller than d cannot assure d connectivity
        if (usedMask.size() < d) break;

        if (verify(nb, mask, d, usedMask)) {
            std::cout << usedMask.size() << std::endl;
            std::vector<int> sorted(usedMask.begin(), usedMask.end());
            std::sort(sorted.begin(), sorted.end());
            for (size_t i=0; i<sorted.size(); ++i) {
                std::cout << sorted[i] << " ";
            }
            std::cout << std::endl;
            return 0;
        }
        it.advance();
    }

    std::cout << "NIE" << std::endl;

    return 0;
}