#include <string>
#include <vector>
#include <list>
#include <cmath>
#include <algorithm>
#include <map>
#include <set>
#include <iostream>
#include <cstdio>
#include <cstdlib>
using namespace std;


class Subgraphs {
  public:
    vector <string> findGroups(int k);
};

vector <string> Subgraphs::findGroups(int k)
{
  vector <string> A;

  return A;
}