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#include <cstdio>
#include <algorithm>
#include <cstdlib>
#include <deque>
#include <vector>
#include <set>
using namespace std;

struct Node {
	set<int> neighbours;
	int degree;
	int group;
	bool isRemoved;
	int howManyTimesWasVisited;
};

Node nodes[200000];
deque<int> aloneNodes;
int n, m, d;
vector<int> solution;
deque<int> dfsNodes;

void removeNode(int id) {
	if (nodes[id].isRemoved) {
		return;
	}
	nodes[id].isRemoved = true;
	for (auto destination = nodes[id].neighbours.begin(); destination != nodes[id].neighbours.end(); ++destination) {
		int target = *destination;
		nodes[target].neighbours.erase(nodes[target].neighbours.find(id));
		nodes[target].degree--;
		if (nodes[target].degree < d) {
			aloneNodes.push_back(target);
		}
	}
}

int dfs(int id) {
	dfsNodes.clear();
	dfsNodes.push_back(id);

	int sum = 0;
	while (!dfsNodes.empty()) {
		int node = dfsNodes.front();
		dfsNodes.pop_front();
		nodes[node].howManyTimesWasVisited = 2;
		sum++;
		for (auto destination = nodes[node].neighbours.begin(); destination != nodes[node].neighbours.end(); ++destination) {
			if (nodes[*destination].howManyTimesWasVisited == 0) {
				dfsNodes.push_back(*destination);
				nodes[*destination].howManyTimesWasVisited = 1;
			}
		}
	}
	
	return sum;
}

void findSolution(int id) {
	dfsNodes.clear();
	dfsNodes.push_back(id);

	while (!dfsNodes.empty()) {
		int node = dfsNodes.front();
		dfsNodes.pop_front();
		solution.push_back(node);
		nodes[node].howManyTimesWasVisited = 4;
		for (auto destination = nodes[node].neighbours.begin(); destination != nodes[node].neighbours.end(); ++destination) {
			if (nodes[*destination].howManyTimesWasVisited == 2) {
				dfsNodes.push_back(*destination);
				nodes[*destination].howManyTimesWasVisited = 3;
			}
		}
	}
}

int main() {
	scanf("%d %d %d", &n, &m, &d);
	for (int i = 0; i < m; ++i) {
		int source, destination;
		scanf("%d %d", &source, &destination);
		source--;
		destination--;
		nodes[source].neighbours.insert(destination);
		nodes[source].degree++;
		nodes[destination].neighbours.insert(source);
		nodes[destination].degree++;
	}

	for (int i = 0; i < n; ++i) {
		if (nodes[i].degree < d) {
			aloneNodes.push_back(i);
		}
	}

	while (!aloneNodes.empty()) {
		int nodeId = aloneNodes.front();
		aloneNodes.pop_front();
		removeNode(nodeId);
	}
	
	int groupSize = -1;
	int groupId = -1;
	for (int i = 0; i < n; ++i) {
		if (!nodes[i].isRemoved && nodes[i].howManyTimesWasVisited == 0) {
			int currentSize = dfs(i);
			if (currentSize > groupSize) {
				groupSize = currentSize;
				groupId = i;
			}
		}
	}

	if (groupId == -1) {
		printf("NIE");
		return 0;
	}

	findSolution(groupId);
	sort(solution.begin(), solution.end());
	printf("%d\n", solution.size());
	int size = solution.size();
	for (int i = 0; i < size; ++i) {
		printf("%d", solution[i]+1);
		if (i < size - 1) {
			printf(" ");
		}
	}
	return 0;
}