#include <iostream>
#include <vector>
#include <queue>
using namespace std;
int N, M;
vector <int> ds[251];
void nhap ()
{
cin>>N>>M;
int a, b;
for (int i=1; i<=M; i++)
{
cin>>a>>b;
ds[a].push_back(b);
ds[b].push_back(a);
}
}
int dd[251];
void khoitao ()
{
for (int i=1; i<=N; i++)
{
dd[i]=0;
}
}
void BFS_Q (int i)
{
queue <int> q;
q.push(i);
dd[i]=1;
while (!q.empty())
{
int next=q.front();
q.pop();
for (int i=0; i<ds[next].size(); i++)
{
int t=ds[next][i];
if (dd[t]==0) q.push (t);
dd[t]=1;
}
}
}
int main ()
{
//IN;
nhap ();
//OUT;
khoitao();
BFS_Q(1);
int kt=0;
for (int i=1; i<=N; i++)
{
if (dd[i]==0)
{
cout<<i<<endl;
kt=1;
}
}
if (kt==0) cout<<"0";
return 0;
}