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/*		Mistrzostwa [B]
 *		Marek Iwaniuk
 *		O(n)
 */

//#include "stdafx.h"
#include <iostream>
#include <cstdio>
#include <queue>

//#define scanf scanf_s
#define INF 999999999
#define MAX_T 200100
using namespace std;

class Cities {
	private:
		int n, m, from, to, k, max_res = 0, res = 0, beg = 0;
		int DelCount[MAX_T];
		bool Delete[MAX_T];
		bool Visited[MAX_T];
		queue<pair<int, int> > Heap;
		vector<int> Coincidence[MAX_T];
	public:
		Cities() {
			scanf("%d %d %d", &n, &m, &k);
			for (int i = 0; i < m; i++) {
				scanf("%d %d", &from, &to);
				Coincidence[from].push_back(to);
				Coincidence[to].push_back(from);
			}
			for (int i = 1; i <= n; i++) {
				Delete[i] = Visited[i] = false;
				DelCount[i] = 0;
				if (Coincidence[i].size() < k) {
					Heap.push(make_pair(Coincidence[i].size(), i));
					Delete[i] = true;
				}	
			}
		}
		
		void DeleteUnuseful() {
			while (Heap.size() > 0) {
				pair<int, int> Top = Heap.front();
				Heap.pop();
				Top.first -= DelCount[Top.second];
				DelCount[Top.second] = INF;

				for (int i = 0; i < Coincidence[Top.second].size(); i++) {
					int frnd = Coincidence[Top.second][i];
					DelCount[frnd]++;
					if (Coincidence[frnd].size() - DelCount[frnd] < k && Delete[frnd] == false) {
						Heap.push(make_pair(Coincidence[frnd].size(), Coincidence[Top.second][i]));
						Delete[frnd] = true;
					}
				}
			}
		}

		int BFS(int from) {
			int res = 1;
			queue<int> Heap;
			Heap.push(from);
			Visited[from] = true;
			DelCount[from] = from;

			while (!Heap.empty()) {
				int top = Heap.front();
				Heap.pop();
				int frnd_count = 0;
				for (int i = 0; i < Coincidence[top].size(); i++) {
					int frnd = Coincidence[top][i];
					frnd_count++;
					if (!Visited[frnd] && !Delete[frnd]) {
						Heap.push(frnd);
						Visited[frnd] = true;
						DelCount[frnd] = from;
						res++;
					}
				}
			}
			return res;
		}

		void BFS() {
			beg = 0;
			for (int i = 1; i <= n; i++) {
				if (!Delete[i] && !Visited[i]) {
					res = BFS(i);
					if (res >= max_res) {
						max_res = res;
						beg = i;
					}
				}
			}
		}

		void Answer() {
			if (max_res == 0) {
				printf("NIE");
			}
			else {
				printf("%d\n", max_res);
				for (int i = 1; i <= n; i++) {
					if (DelCount[i] == beg) {
						printf("%d ", i);
					}
				}
			}
		}
};

int main() {
	Cities *New = new Cities();
	New->DeleteUnuseful();
	New->BFS();
	New->Answer();
	return 0;
}