#include<bits/stdc++.h>
using namespace std;
vector<int> ke[1001];
bool visited[1001];
int parent[1001];
bool DFS(int u){
	visited[u] = true;
	for(int x : ke[u]){
        if(!visited[x]){
            parent[x] = u;
            if(DFS(x)){
                return true;
            }
        }
        else if(u != parent[x]){
            return true;
        }
	}
	return false;
}
 
int main(){
	int m , n;
	cin >> m >> n ;
	for(int i = 1 ; i <= n ; i++){
		int x,y;
		cin >> x >> y ;
		ke[x].push_back(y);
		ke[y].push_back(x);
	}
	if(DFS(1)){
        cout << "1";
	}
	else cout << "0";
}
 

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MTAgMTEKMTAgNQoxMCA0CjEwIDEKMTAgMwo1IDIKNSA0CjEwIDgKNSAzCjUgMQoKMTAgNgoxMCA5

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10 1
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5 2
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5 3
5 1

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