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//#include <gtest/gtest.h>

#include <iostream>
#include <vector>
#include <queue>

using std::vector;
using std::queue;

bool bfsBipartiteCheck(vector<vector<int>> &adj, int s) {
	if (adj[s].size() == 0)
		return true;

	vector<int> dist(adj.size(), -1);
	dist[s] = 0;
	queue<int> vertexQ;

	vertexQ.push(s);

	while (!vertexQ.empty()) {
		int u = vertexQ.front();
		vertexQ.pop();
		for (int i : adj[u]) {
			if (dist[i] == -1) {
				vertexQ.push(i);
				if (dist[u] == 0)
					dist[i] = 1;
				if (dist[u] == 1)
					dist[i] = 0;
			} else if (dist[i] == dist[u])
				return false;
		}
	}
	return true;
}

int bipartite(vector<vector<int> > &adj) {
	bool bipartiteCheckNodes = bfsBipartiteCheck(adj, 0);
	if (bipartiteCheckNodes)
		return 1;
	else
		return 0;
}

int main() {
	int n, m;
	std::cin >> n >> m;
	vector<vector<int> > adj(n, vector<int>());
	for (int i = 0; i < m; i++) {
		int x, y;
		std::cin >> x >> y;
		adj[x - 1].push_back(y - 1);
		adj[y - 1].push_back(x - 1);
	}
	std::cout << bipartite(adj);
}

//TEST(Acyclicity, ac1) {
//	vector<vector<int>> adj = { { 1 }, { 2 }, { 0 }, { 0 } };
//	ASSERT_EQ(acyclic(adj), 1);
//}