#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>

using namespace std;

int main(int argc, char* argv[])
{
  if (argc != 3)
  {
    cerr << "ERROR: No filename given." << endl;
    return 1;
  }

  ifstream f(argv[1]);
  if ( ! f )
  {
    cerr << "ERROR: Could not open '" << argv[1] << "'." << endl;
    return 1;
  }

  string first, last;
  vector<pair<string, string>> v;

  while (f >> first >> last)
  {
    if ( first == argv[2] )
      v.emplace_back(last, first);
  }
  f.close();
  
  sort(v.begin(), v.end());
  
  for ( pair<string,string> const& i : v )
  {
    cout << i.second << " " << i.first << endl;
  }
  return 0;
}