bpavuk.neocities.org
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src/02/solution.cxx
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src/02/solution.cxx
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#include <format>
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#include <fstream>
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#include <functional>
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#include <iterator>
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#include <print>
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#include <ranges>
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#include <regex>
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#include <string>
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#include <vector>
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#ifndef DATA_FOLDER
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#error \
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bool part2_valid;
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};
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NumberProfile is_valid(long id) {
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[[nodiscard]] NumberProfile is_valid(long id) {
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std::string id_string = std::to_string(id);
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bool part1_valid = true;
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bool part2_valid = true;
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for (unsigned long i = 1; i <= id_string.length(); ++i) {
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auto substring = id_string.substr(0, i);
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auto regex_str_part_1 = std::format("({}){{2}}", substring);
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auto regex_str_part_2 = std::format("({}){{2,}}", substring);
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auto regex_part_1 = std::regex(regex_str_part_1);
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auto regex_part_2 = std::regex(regex_str_part_2);
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if (part1_valid) {
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part1_valid = !std::regex_match(id_string, regex_part_1);
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}
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if (part2_valid) {
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part2_valid = !std::regex_match(id_string, regex_part_2);
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}
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if (!part1_valid && !part2_valid) {
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break;
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}
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// repeats 2 times
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if (id_string.length() % 2 == 0 && part1_valid) {
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bool invalid = id_string.substr(0, id_string.length() / 2) ==
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id_string.substr(id_string.length() / 2);
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part1_valid = !invalid;
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}
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// repeats more than 2 times
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if (id_string.length() >= 2 && part2_valid) {
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auto t = id_string + id_string;
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part2_valid =
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t.substr(1, t.length() - 2).find(id_string) == std::string::npos;
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}
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return NumberProfile{
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};
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}
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// Ryzen 5 5600G runtime: 25m51s
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// Ryzen 5 5600G runtime: 1s494ms
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int main() {
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std::ifstream input(input_path);
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if (!input.is_open()) {
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auto left = t.substr(0, t.find('-'));
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auto right = t.substr(t.find('-') + 1);
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auto ids = std::ranges::views::iota(std::stol(left), std::stol(right) + 1) |
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std::ranges::views::transform(is_valid);
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auto ids = std::vector<NumberProfile>(std::stol(right) - std::stol(left));
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{
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auto ids_num = std::vector<long>(std::stol(right) - std::stol(left));
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std::ranges::iota(ids_num.begin(), ids_num.end(), std::stol(left));
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std::ranges::transform(ids_num, std::back_inserter(ids),
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[](auto i) { return is_valid(i); });
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}
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auto invalid_ids_part1 =
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ids | std::ranges::views::filter([](NumberProfile i) {
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return !i.part1_valid;
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}) |
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std::ranges::views::transform([](NumberProfile i) { return i.number; });
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auto sum_part1 = std::ranges::fold_left(invalid_ids_part1, 0, std::plus{});
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auto sum_part1 =
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std::ranges::fold_left(invalid_ids_part1, 0ULL, std::plus<>{});
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password_part_1 += sum_part1;
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auto sum_part2 = std::ranges::fold_left(invalid_ids_part2, 0, std::plus{});
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auto sum_part2 =
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std::ranges::fold_left(invalid_ids_part2, 0ULL, std::plus<>{});
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password_part_2 += sum_part2;
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}
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