hash_set<uint> found;
bool foo(uint hash) {
  if (found.find(hash) != found.end())
    return true;
  found.insert(hash);
  return false;
}


vector<vector<string> > doit(vector<vector<string> > inp) {
  vector<vector<uint> > hashes;
  vector<vector<bool> > marked;
  for (int i = 0; i < inp.size(); ++i) {
    hashеs.push_back(vector<uint>());
    marked.push_back(vector<bool>());
    for (int j = 0; j < inp[i].size(); ++j) {
      uint h = 0;
      for (int k = 0; k < inp[i][j].size(); ++k) {
        h *= base;
        h += inp[i][j][k];
      }
      hashes.back().push_back(h);
      marked.push_back(false);
    }
  }

  for (int i = 0; i < hashes.size(); ++i) {
    if (hashes[i].size() <= 2) continue;
    uint rh = 0;
    uint base3 = 1;
    for (int j = 0; j < 2; ++j) {
      rh *= base;
      rh += hashes[i][j];
      base3 *= base;
    }
    for (int j = 2; j < hashes[i].size(); ++j) {
      rh *= base;
      rh += hashes[i][j];

      if (foo(rh)) {
        marked[i][j-2] = marked[i][j-1] = marked[i][j] = true;
      }

      rh -= hashes[i][j-2] * base3;
    }
  }

  vector<vector<string> > out;
  for (int i = 0; i < marked.size(); ++i) {
    out.push_back(vector<string>());
    for (int j = 0; j < marked[i].size(); ++j) {
      if (!marked[i][j]) {
        out.back().push_back(inp[i][j]);
      }
    }
  }
  
  return out;
}