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#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;
vector< vector < int > > roadsFromCity(200001);
vector<int> roadsNumber(200001);
vector<int> subgraphNum(200001);
vector<bool> removed(200001);
int n, m, d;
int groupNum;
bool DFS(int);
void DFSErase(int);
int main()
{
  for(int i = 0 ; i <= 200000; i++)
  {
    roadsNumber[i] = 0;
    subgraphNum[i] = 0;
    removed[i] = false;
  }
  //wczytywanie danych
  int city1, city2;
  cin >> n >> m >> d;
  for(int i = 0 ; i < m ; i ++)
  {
    cin >> city1 >> city2;
    roadsFromCity[city1].push_back(city2);
    roadsFromCity[city2].push_back(city1);
  }
  //usuwanie miast o mniej niż d drogach
  for(int i = 1; i <= n; i++)
  {
    roadsNumber[i] = roadsFromCity[i].size() ;
  }

  for(int i = 1; i <= n; i++)
  {
    DFSErase(i);
  }
  
  groupNum = 1;
  //szukanie wiekszego podgrafu conajmniej d stopnia
  for(int i = 1; i <= n ; i++)
  {
    if(subgraphNum[i] == 0)
    {
      if(DFS(i)) // zbuduj spojne podgrafy
        groupNum++;
    }
  }
  if(groupNum == 1) // brak miast
    cout << "NIE" << endl;
  else
  {
    vector<int> groupQuantity(groupNum);
    for (int i = 1; i <= n ; i++) // zlicz ilosc wierzcholkow w spojnych podgrafach
    {
      groupQuantity[subgraphNum[i]] ++;
    }
    int maxGroup = 1;
    for(unsigned int i = 1; i < groupQuantity.size(); i++)
    {
      if(groupQuantity[maxGroup] < groupQuantity[i])
        maxGroup = i;
    }
    cout << groupQuantity[maxGroup] << endl;
    for(int i = 1; i <= n ; i++)
    {
      if(subgraphNum[i] == maxGroup)
      {
        cout << i << " ";
      }
    }
    cout << endl;
  }
  return 0;
}


bool DFS(int edgeNum)
{
  if(roadsNumber[edgeNum] < d)
  {
    return false;
  }
  subgraphNum[edgeNum] = groupNum;
  for(unsigned int i = 0; i < roadsFromCity[edgeNum].size(); i++)
  {
    if(subgraphNum[roadsFromCity[edgeNum][i]] != groupNum)
    DFS(roadsFromCity[edgeNum][i]);
  }
  return true;
}

void DFSErase(int edgeNum)
{
  if(roadsNumber[edgeNum] < d && removed[edgeNum] == false)
  {
    removed[edgeNum] = true;
    for(unsigned int j = 0 ; j < roadsFromCity[edgeNum].size(); j++)
    {
      roadsNumber[roadsFromCity[edgeNum][j]]--;
      DFSErase(roadsFromCity[edgeNum][j]);
    }
  }
}