This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define suiii ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define ll long long
#define co cout<<
//#pragma GCC optimize("O3,Ofast,unroll-loops")
//#pragma GCC target("avx2,sse3,sse4,avx")
using namespace std;
//stuff
ll n,m;
bool del[3005];
bool mat[3005][3005];
void solve(){
    cin>>n>>m;
    for(int i=1;i<=m;i++){
        ll a,b;
        cin>>a>>b;
        mat[a][b]=1;
        mat[b][a]=1;
    }
    for(int i=1;i<=n;i++){
        if(del[i]) continue;
        for(int j=i+1;j<=n;j++){
            if(del[j]) continue;
            if(mat[i][j]==0){
                del[i]=1;
                del[j]=1;
                break;
            }
        }
    }
    ll num=0;
    for(int i=1;i<=n;i++){
        if(del[i]==0&&num<n/3){
            co i<<' ';
            num++;
        }
    }
}
int main()
{
    suiii
    int t=1;
    // cin>>t;
    while(t--){
        solve();
    }
    return 0;
}
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