private List<Player> matchmaker(List<Integer> elos, List<String> names) {
       List<Player> players = new ArrayList<Player>();

       for (int i = 0; i < elos.size(); i++) {
           Player player = new Player();
           player.elo = elos.get(i);
           player.name = names.get(i);

           players.add(player);
       }

       Collections.sort(players);
       return players;
   }

   private class Player implements Comparable<Player> {

       private Integer elo;
       private String name;

       @Override
       public int compareTo(Player other) {
           return elo.compareTo(other.elo);
       }
   }