#include #include #include #include #include #include #include #include #include #include #include namespace { namespace qi = boost::spirit::qi; namespace phx = boost::phoenix; namespace ascii = boost::spirit::ascii; struct Card { unsigned long long id; std::vector mine; std::vector winners; }; struct Grammar : public qi::grammar(), ascii::space_type> { qi::rule card; qi::rule(), ascii::space_type> cards; Grammar() : base_type{cards} { using namespace qi::labels; cards = *card; card = "Card" >> qi::ulong_long [ phx::bind(&Card::id, _val) = _1] >> ":" >> (*qi::ulong_long) [ phx::bind(&Card::mine, _val) = _1] >> "|" >> (*qi::ulong_long) [ phx::bind(&Card::winners, _val) = _1]; } }; auto CountWins(std::vector& cards) -> std::vector { std::vector result; result.reserve(cards.size()); for (auto& card : cards) { std::vector xs; std::sort(card.mine.begin(), card.mine.end()); std::sort(card.winners.begin(), card.winners.end()); std::set_intersection(card.mine.begin(), card.mine.end(), card.winners.begin(), card.winners.end(), std::back_inserter(xs)); result.push_back(xs.size()); } return result; } auto Part1(std::vector const& wins) -> std::uint64_t { std::uint64_t result = 0; for (auto const win : wins) { if (win > 0) { result += std::uint64_t{1} << (win - 1); } } return result; } auto Part2(std::vector const& wins) -> std::size_t { std::vector psums(wins); psums.push_back(0); for (std::size_t i = wins.size(); i --> 0;) { psums[i] = 1 + 2 * psums[i+1] - psums[1 + i + psums[i]]; } return psums.front(); } } // namespace TEST_SUITE("2023-04 examples") { TEST_CASE("example") { std::istringstream in { R"(Card 1: 41 48 83 86 17 | 83 86 6 31 17 9 48 53 Card 2: 13 32 20 16 61 | 61 30 68 82 17 32 24 19 Card 3: 1 21 53 59 44 | 69 82 63 72 16 21 14 1 Card 4: 41 92 73 84 69 | 59 84 76 51 58 5 54 83 Card 5: 87 83 26 28 32 | 88 30 70 12 93 22 82 36 Card 6: 31 18 13 56 72 | 74 77 10 23 35 67 36 11 )" }; auto input = aocpp::ParseGrammar_(Grammar{}, in); auto const wins = CountWins(input); CHECK(Part1(wins) == 13); CHECK(Part2(wins) == 30); } } auto Main(std::istream & in, std::ostream & out) -> void { auto input = aocpp::ParseGrammar_(Grammar{}, in); auto const wins = CountWins(input); out << "Part 1: " << Part1(wins) << std::endl; out << "Part 2: " << Part2(wins) << std::endl; }