#pragma comment(linker, "/STACK:10000000")
#define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;

vector< vector<int> > graph;
vector<int> articulation_point;
bool *used;
int time, *tin;

int dfs(int v, int p = -1)
{
	bool v_used = false;
	used[v] = true;
	tin[v] = time++;
	int min_time = tin[v];
	int children = 0;
	for (size_t i = 0; i < graph[v].size(); ++i)
	{
		int to = graph[v][i];
		if (to == p)
			continue;
		if (used[to])
			min_time = min(min_time, tin[to]);
		else
		{
			int b = dfs(to, v);
			min_time = min(min_time, b);
			if (b >= tin[v] && p != -1)
			{
				if (!v_used)
					articulation_point.push_back(v);
				v_used = true;
			}
			++children;
		}
	}
	if (p == -1 && children > 1)
	{
		if (!v_used)
			articulation_point.push_back(v);
		v_used = true;
	}
	return min_time;
}

int main()
{
	FILE *fin = fopen("input.txt", "r");
	FILE *fout = fopen("output.txt", "w");
	int n, m;
	fscanf(fin, "%d%d", &n, &m);
	graph.resize(n);
	tin = new int[n];
	used = new bool[n];
	for (int i = 0; i < n; ++i)
	{
		tin[i] = -1;
		used[i] = false;
	}
	for (int i = 0; i < m; ++i)
	{
		int buff1, buff2;
		fscanf(fin, "%d%d", &buff1, &buff2);
		graph[--buff1].push_back(--buff2);
		graph[buff2].push_back(buff1);
	}
	fclose(fin);
	dfs(0);
	delete[] tin;
	delete[] used;
	fprintf(fout, "%d ", articulation_point.size());
	for (vector<int>::iterator i = articulation_point.begin(); i != articulation_point.end(); ++i)
		fprintf(fout, "%d ", *i + 1);
	fclose(fout);
	return 0;
}