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#include <cstdio>
#include <list>
#include <algorithm>

#define DEBUG

#ifdef DEBUG
#undef DEBUG
#endif

using namespace std;

long long n, m, d;
long long a, b;

#define MAX_N 200001

typedef list<long long> type_G;

type_G G[MAX_N];
long long Conn[MAX_N];
bool Invalid[MAX_N];
bool Grouped[MAX_N];
long long GroupSize[MAX_N];
type_G Groups[MAX_N];

void CheckCity(long long index) {
    type_G::iterator it;
    /* Do not invalidate already invalidated city */
    if (Invalid[index])
        return;
    if (Conn[index] < d) {
        Invalid[index] = true;
        /* Remove 1 from all cities that we were connected to */
        for (it=G[index].begin(); it!=G[index].end(); it++) {
            Conn[*it]--;
        }
        /* Check all connected cities if they are still valid */
        for (it=G[index].begin(); it!=G[index].end(); it++) {
            /* Check once again only cities that have already been checked */
            if (*it < index) {
                /* 
                 * We do new check of city only once for every connection that 
                 * it has, so there are maximum m additional checks
                 */
                CheckCity(*it);
            }
        }        
    }
}

void AssignGroup(long long index, long long group_index) {
    type_G::iterator it;
    Grouped[index] = true;
    Groups[group_index].push_back(index);
    GroupSize[group_index]++;
    for (it=G[index].begin(); it!=G[index].end(); it++) {
        if ( (!Invalid[*it]) && (Grouped[*it]==0) ) {
            AssignGroup(*it, group_index);
        }
    }
}

void GroupCities() {
    long long i;
    type_G::iterator it;
    long long group_id = 0;
    for (i=0; i<n; i++) {
        if ( (!Invalid[i]) && (!Grouped[i])) {
            AssignGroup(i, group_id);
            group_id++;
        }
    }
}

int main() {
    long long i;
    long long max_group_index = 0;

    scanf("%lld%lld%lld", &n, &m, &d);
    for (i=0; i<m; i++) {
        scanf("%lld%lld", &a, &b);
        G[a].push_back(b);
        G[b].push_back(a);
        Conn[a]++;
        Conn[b]++;
    }

    /* Check all cities if they have >= d connections */
    for (i=0; i<n; i++) {
        CheckCity(i);
    }

    /* Group cities */
    GroupCities();

#ifdef DEBUG
    printf("Printing Groups begin\n");
    for (i=0; GroupSize[i]>0; i++) {
        printf("Group[%lld]:", i);
        type_G::iterator it;
        for (it=Groups[i].begin(); it!=Groups[i].end(); it++) {
            printf(" %lld", *it);
        }
        printf("\n");
    }
    printf("Printing Groups end\n\n");
#endif

    /* Find maximum sized group */
    for (i=1; GroupSize[i]>0; i++) {
        if (GroupSize[i] > GroupSize[max_group_index]) {
            max_group_index = i;
        }
    }

    /* Check if there is at least one group */
    if (GroupSize[max_group_index] == 0) {
        printf("NIE\n");
        return 0;
    }

    /* Print all members of this group */
    type_G::iterator it;
    Groups[max_group_index].sort();
    it = Groups[max_group_index].begin();
    printf("%lld\n", GroupSize[max_group_index]);
    printf("%lld", *it);
    it++;
    for (; it != Groups[max_group_index].end(); it++) {
        printf(" %lld", *it);
    }
    printf("\n");
}