import java.util.ArrayList;
import java.util.Map;
import java.util.TreeMap;

/**
 * Holds the tally of votes for an election.
 * 
 * @author Scot Drysdale
 */
public class VoteTally {
  Map<String, Integer> tally;
  
  /**
   * Construct a tally with no votes.
   */
  public VoteTally() {
    tally = new TreeMap<String, Integer>();
  }
  
  /**
   * Record a vote for a candidate.  If candidate not found,
   *   add that candidate with a vote total of 1.
   * @param candidate the name of the candidate to receive a vote
   */
  public void recordVote(String candidate) {
    Integer currentTally = tally.get(candidate);
    if (currentTally != null)
      tally.put(candidate,  currentTally + 1);
    else
      tally.put(candidate, 1);    // new candidate--add with 1 vote
  }
  
  /**
   * Find the candidates with the fewest votes.
   * @return a list of candidates with the fewest votes.
   */
  public ArrayList<String> getLosers() {
    ArrayList<String> loserList = new ArrayList<String>();
    int minTally = Integer.MAX_VALUE;  // bigger than any possible vote count
    
    for (String candidate : tally.keySet()) {
      int candidateTally = tally.get(candidate);
      if (candidateTally < minTally) {  // found a possible loser?
        loserList.clear();              // forget the previous possible losers
        loserList.add(candidate);       // remember the new loser
        minTally = candidateTally;      
      }
      else if (candidateTally == minTally)
        loserList.add(candidate);       // have another with the same low tally
    }
    return loserList;
  }
  
  /**
   * Return the election results.
   */
  public String toString() {
    return "Candidate names with vote tallies: \n" + tally.toString();
  }
}