//Prompt the user for a file, create a voter preference Map, and print it.
//Determine the Set of all the candidates in the election, from this Map.
//Repeatedly evaluate the ballot based on the candidates (still) in the
// election, printing the vote count (tally) two ways: with the candidates
// (a) shown alphabetically increasing and (b) shown with the vote count
// decreasing (candidates with equal vote counts are shown alphabetically
// increasing); from this tally, compute which candidates remain in the
// election: all candidates receiving more than the minimum number of votes;
// continue this process until there are less than 2 candidates.
//Print the final result: there may 1 candidate left (the winner) or 0 left
// (no winner).
int main() {
try {
std::ifstream text_file;
ics::safe_open(text_file,"Enter the name of a file with voter preferences","votepref1.txt");
std::cout << std::endl;
const Preferences prefs = read_voter_preferences(text_file);
print_voter_preferences(prefs);
std::cout << std::endl;
CandidateSet candidateSet;
for (const auto& kv : prefs) {
for (const std::string& candidate : kv.second) {
candidateSet.insert(candidate);
}
}
CandidateTally tally = evaluate_ballot(prefs, candidateSet);
int ballot = 1;
while (candidateSet.size() > 1) {
std::stringstream ss;
ss << ballot++;
print_tally("Vote count on ballot #" + ss.str() +
" with candidates in alphabetical order", tally, alphabetic_gt);
print_tally("Vote count on ballot #" + ss.str() +
" with candidates in numerical order", tally, numeric_gt);
candidateSet = remaining_candidates(tally);
tally = evaluate_ballot(prefs, candidateSet);
}
if (candidateSet.size() == 0) {
std::cout << "No winner" << std::endl;
} else {
std::string winner;
for (const std::string& candidate : candidateSet) {
winner += candidate + " and ";
}
std::cout << "Winner is " << winner.substr(0, winner.length()-5) << std::endl;
}
} catch (ics::IcsError& e) {
std::cout << e.what() << std::endl;
}
return 0;
}
void
RandomPairCandidateSetScorer::Score(Model *model,
CandidateSet &candidates, bool training) {
// First, pick two candidate indices at random.
size_t idx1 = GetRandomIndex(candidates.size());
size_t idx2 = GetRandomIndex(candidates.size());
Candidate &c1 = candidates.Get(idx1);
Candidate &c2 = candidates.Get(idx2);
// Next, just score those two candidates.
model->ScoreCandidate(c1, training);
model->ScoreCandidate(c2, training);
// Finally, set indices of best scoring and gold amongst just those two.
int score_cmp = model->score_comparator()->Compare(*model, c1, c2);
candidates.set_best_scoring_index(score_cmp > 0 ? c1.index() : c2.index());
int gold_cmp = model->gold_comparator()->Compare(*model, c1, c2);
candidates.set_gold_index(gold_cmp > 0 ? c1.index() : c2.index());
}
