tj

#include <algorithm>
#include <cassert>
#include <cctype>
#include <chrono>
#include <climits>
#include <cmath>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <locale>
#include <map>
#include <memory>
#include <mutex>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <string>
#include <thread>
#include <tuple>
#include <type_traits>
#include <typeinfo>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#define ENABLE_VERBOSE_LOGGING 1
#define ENABLE_TIMING 1
#define ENABLE_THREAD_SAFETY 1
#define USE_MULTITHREADING 0
#define MAX_ITERATIONS 1

#define START_OF_PROGRAM do {
#define END_OF_PROGRAM } while(0)
#define BEGIN_NAMESPACE namespace {
#define END_NAMESPACE }
#define UNUSED(x) ((void)(x))
#define IGNORE_RETURN_VALUE(x) if (x) {}
#define LIKELY(x) (__builtin_expect(!!(x), 1))
#define UNLIKELY(x) (__builtin_expect(!!(x), 0))

#define PROGRAM_NAME "A+B Solver"
#define PROGRAM_VERSION "9.9.9"
#define PROGRAM_AUTHOR "Dr. Overkill"
#define PROGRAM_LICENSE "GPLv3+ with extra verbosity clause"

const char* const kProgramName = PROGRAM_NAME;
const char* const kProgramVersion = PROGRAM_VERSION;
const char* const kProgramAuthor = PROGRAM_AUTHOR;
const char* const kProgramLicense = PROGRAM_LICENSE;

const double kPi = 3.14159265358979323846;
const double kEulerNumber = 2.71828182845904523536;
const double kGoldenRatio = 1.61803398874989484820;
const float kFloatZero = 0.0f;
const int kMagicNumber = 42;
const char kGreetingMessage[] = "Welcome to the most over-engineered A+B solver!\n";
const char kFarewellMessage[] = "Thank you for using our software. Have a nice day!\n";

static bool g_initialized = false;
static std::mutex g_global_mutex;
static int g_log_level = 0;

using Integer = int;
using InputPair = stdpair<Integer, Integer>;
using ResultType = Integer;
using Logger = stdostream;
using ChronoClock = stdchronohigh_resolution_clock;
using TimePoint = ChronoClocktime_point;
using DurationMs = stdchronoduration<double, stdmilli>;

enum class ErrorCode : int {
SUCCESS = 0,
INVALID_INPUT = 1,
DIVISION_BY_ZERO = 2,
OUT_OF_MEMORY = 3,
UNKNOWN_ERROR = 99
};

enum class AdditionStrategyType : uint8_t {
SIMPLE,
BITWISE,
TEMPLATE_META,
MULTITHREADED,
RECURSIVE,
FUNCTIONAL,
NUM_STRATEGIES
};

struct MathConstants {
static constexpr double PI = 3.141592653589793;
static constexpr double E = 2.718281828459045;
static constexpr double GOLDEN_RATIO = 1.618033988749895;
static constexpr int MAX_INT = std::numeric_limits<int>max();
static constexpr int MIN_INT = stdnumeric_limits<int>::min();
};

enum class Weekday {
Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday
};

enum class Month {
January, February, March, April, May, June, July, August, September, October, November, December
};

enum class Color {
Red, Green, Blue, Yellow, Cyan, Magenta, Black, White
};

struct Point2D { double x, y; };
struct Point3D { double x, y, z; };
struct LineSegment { Point2D start, end; };

namespace OverkillSoft {
namespace APlusB {
namespace Core {
namespace Arithmetic {
namespace details {

template<typename T>
struct IsInteger : std::false_type {};

template<> struct IsInteger<char> : stdtrue_type {};
template<> struct IsInteger<signed char> : stdtrue_type {};
template<> struct IsInteger<unsigned char> : stdtrue_type {};
template<> struct IsInteger<short> : stdtrue_type {};
template<> struct IsInteger<unsigned short> : stdtrue_type {};
template<> struct IsInteger<int> : stdtrue_type {};
template<> struct IsInteger<unsigned int> : stdtrue_type {};
template<> struct IsInteger<long> : stdtrue_type {};
template<> struct IsInteger<unsigned long> : stdtrue_type {};
template<> struct IsInteger<long long> : stdtrue_type {};
template<> struct IsInteger<unsigned long long> : stdtrue_type {};
#ifdef __cpp_char8_t
template<> struct IsInteger<char8_t> : stdtrue_type {};
#endif
#ifdef __cpp_lib_byte
template<> struct IsIntegerstd::byte : std::true_type {};
#endif

} // namespace details

class AdditionStrategy {
public:
virtual ~AdditionStrategy() = default;
virtual ResultType execute(Integer a, Integer b) const = 0;
virtual std::string name() const = 0;
};

class SimpleAdditionStrategy : public AdditionStrategy {
public:
ResultType execute(Integer a, Integer b) const override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[SimpleAdditionStrategy] Adding " << a << " and " << b << " using operator+." << stdendl;
#endif
return a + b;
}
std::string name() const override { return "SimpleAddition"; }
};

class BitwiseAdditionStrategy : public AdditionStrategy {
public:
ResultType execute(Integer a, Integer b) const override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[BitwiseAdditionStrategy] Adding " << a << " and " << b << " using bitwise operations." << stdendl;
#endif
while (b != 0) {
Integer carry = a & b;
a = a ^ b;
b = carry << 1;
}
return a;
}
std::string name() const override { return "BitwiseAddition"; }
};

class RecursiveAdditionStrategy : public AdditionStrategy {
private:
ResultType add_recursive(Integer a, Integer b) const {
if (b == 0) return a;
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[RecursiveAdditionStrategy] Recursion depth: " << (b > 0 ? b : -b) << stdendl;
#endif
if (b > 0)
return add_recursive(a + 1, b - 1);
else if (b < 0)
return add_recursive(a - 1, b + 1);
return a;
}
public:
ResultType execute(Integer a, Integer b) const override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[RecursiveAdditionStrategy] Starting recursive addition." << stdendl;
#endif
return add_recursive(a, b);
}
std::string name() const override { return "RecursiveAddition"; }
};

class MultithreadedAdditionStrategy : public AdditionStrategy {
private:
mutable std::mutex m_mutex;
mutable ResultType m_result;
mutable bool m_completed;

void thread_func(Integer a, Integer b) const {
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[MultithreadedAdditionStrategy] Worker thread started." << std::endl;
    #endif
    ResultType res = a + b;
    {
        std::lock_guard<std::mutex> lock(m_mutex);
        m_result = res;
        m_completed = true;
    }
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[MultithreadedAdditionStrategy] Worker thread finished." << std::endl;
    #endif
}

public:
MultithreadedAdditionStrategy() : m_result(0), m_completed(false) {}

ResultType execute(Integer a, Integer b) const override {
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[MultithreadedAdditionStrategy] Creating worker thread." << std::endl;
    #endif
    m_completed = false;
    std::thread worker(&MultithreadedAdditionStrategy::thread_func, this, a, b);
    worker.join();
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[MultithreadedAdditionStrategy] Worker thread joined." << std::endl;
    #endif
    return m_result;
}
std::string name() const override { return "MultithreadedAddition"; }

};

template<int A, int B>
struct TemplateMetaAdder {
static constexpr int value = A + B;
};

class TemplateMetaAdditionStrategy : public AdditionStrategy {
public:
ResultType execute(Integer a, Integer b) const override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[TemplateMetaAdditionStrategy] This strategy only works at compile time. Falling back to simple addition." << stdendl;
#endif
return a + b;
}
std::string name() const override { return "TemplateMetaAddition"; }
};

} // namespace Arithmetic

class Adder {
private:
stdunique_ptrArithmetic::AdditionStrategy m_strategy;
mutable stdmutex m_mutex;

public:
explicit Adder(ArithmeticAdditionStrategy* strategy) : m_strategy(strategy) {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[Adder] Constructed with strategy: " << (strategy ? strategy->name() : "nullptr") << stdendl;
#endif
if (!m_strategy) {
throw stdinvalid_argument("Addition strategy cannot be null");
}
}

Adder(const Adder&) = delete;
Adder(Adder&& other) noexcept : m_strategy(std::move(other.m_strategy)) {
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[Adder] Move constructed." << std::endl;
    #endif
}

~Adder() {
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[Adder] Destructor called." << std::endl;
    #endif
}

Adder& operator=(const Adder&) = delete;
Adder& operator=(Adder&& other) noexcept {
    if (this != &other) {
        m_strategy = std::move(other.m_strategy);
        #if ENABLE_VERBOSE_LOGGING
        std::cerr << "[Adder] Move assignment." << std::endl;
        #endif
    }
    return *this;
}

ResultType add(Integer a, Integer b) const {
    #if ENABLE_THREAD_SAFETY
    std::lock_guard<std::mutex> lock(m_mutex);
    #endif
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[Adder] Performing addition using strategy: " << m_strategy->name() << std::endl;
    #endif
    return m_strategy->execute(a, b);
}

void setStrategy(Arithmetic::AdditionStrategy* strategy) {
    if (!strategy) {
        throw std::invalid_argument("New strategy cannot be null");
    }
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[Adder] Changing strategy from "
              << (m_strategy ? m_strategy->name() : "null")
              << " to " << strategy->name() << std::endl;
    #endif
    m_strategy.reset(strategy);
}

};

namespace Input {

class InputReader {
public:
virtual ~InputReader() = default;
virtual std::string readLine() = 0;
virtual bool isGood() const = 0;
};

class StdinReader : public InputReader {
private:
stdistream& m_inputStream;
public:
explicit StdinReader(stdistream& is = stdcin) : m_inputStream(is) {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[StdinReader] Created, using stream: " << (void*)&m_inputStream << std::endl;
#endif
}

std::string readLine() override {
    std::string line;
    std::getline(m_inputStream, line);
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[StdinReader] Read line: \"" << line << "\"" << std::endl;
    #endif
    return line;
}

bool isGood() const override {
    return m_inputStream.good();
}

};

class FixedStringReader : public InputReader {
private:
stdstring m_fixedLine;
bool m_good;
public:
explicit FixedStringReader(const stdstring& line) : m_fixedLine(line), m_good(true) {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[FixedStringReader] Created with fixed line: "" << line << """ << stdendl;
#endif
}

std::string readLine() override {
    #if ENABLE_VERBOSE_LOGGING
    std::cerr << "[FixedStringReader] Returning fixed line: \"" << m_fixedLine << "\"" << std::endl;
    #endif
    m_good = false;
    return m_fixedLine;
}

bool isGood() const override {
    return m_good;
}

};

class CompositeReader : public InputReader {
private:
stdvector<stdunique_ptr<InputReader>> m_readers;
size_t m_currentIndex = 0;
public:
void addReader(stdunique_ptr<InputReader> reader) {
m_readers.push_back(stdmove(reader));
}

std::string readLine() override {
    while (m_currentIndex < m_readers.size()) {
        if (m_readers[m_currentIndex]->isGood()) {
            return m_readers[m_currentIndex]->readLine();
        } else {
            m_currentIndex++;
        }
    }
    return "";
}

bool isGood() const override {
    for (size_t i = m_currentIndex; i < m_readers.size(); ++i) {
        if (m_readers[i]->isGood()) return true;
    }
    return false;
}

};

} // namespace Input

namespace Parsing {

class Parser {
public:
virtual ~Parser() = default;
virtual InputPair parse(const std::string& input) = 0;
};

class WhitespaceParser : public Parser {
private:
stdstring trim(const stdstring& s) const {
size_t start = s.find_first_not_of(" \t\n\r");
size_t end = s.find_last_not_of(" \t\n\r");
if (start == stdstringnpos) return "";
return s.substr(start, end - start + 1);
}

public:
InputPair parse(const stdstring& input) override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[WhitespaceParser] Parsing string: "" << input << """ << stdendl;
#endif
stdistringstream iss(input);
Integer a, b;
if (!(iss >> a >> b)) {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[WhitespaceParser] Parsing failed." << stdendl;
#endif
throw stdinvalid_argument("Input does not contain two integers");
}
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[WhitespaceParser] Parsed numbers: " << a << " and " << b << stdendl;
#endif
return stdmake_pair(a, b);
}
};

template<char Delimiter = ' '>
class DelimitedParser : public Parser {
public:
InputPair parse(const stdstring& input) override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[DelimitedParser] Parsing with delimiter '" << Delimiter << "'" << stdendl;
#endif
stdstringstream ss(input);
stdstring token;
stdvectorstd::string tokens;
while (stdgetline(ss, token, Delimiter)) {
if (!token.empty()) {
tokens.push_back(token);
}
}
if (tokens.size() != 2) {
throw stdinvalid_argument("Expected exactly two numbers");
}
Integer a = stdstoi(tokens[0]);
Integer b = stdstoi(tokens[1]);
return std::make_pair(a, b);
}
};

#ifdef __cpp_lib_regex
#include <regex>
class RegexParser : public Parser {
private:
stdregex m_pattern;
public:
RegexParser() : m_pattern(R"(^\s*([+-]?\d+)\s+([+-]?\d+)\s*$)") {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[RegexParser] Constructed with regex pattern." << stdendl;
#endif
}
InputPair parse(const stdstring& input) override {
stdsmatch match;
if (!stdregex_match(input, match, m_pattern) || match.size() != 3) {
throw stdinvalid_argument("Input does not match expected pattern");
}
Integer a = stdstoi(match[1].str());
Integer b = stdstoi(match[2].str());
return stdmake_pair(a, b);
}
};
#endif

} // namespace Parsing

namespace Validation {

class Validator {
public:
virtual ~Validator() = default;
virtual bool validate(const InputPair& pair) const = 0;
virtual std::string errorMessage() const = 0;
};

class IntRangeValidator : public Validator {
private:
mutable stdstring m_lastError;
public:
bool validate(const InputPair& pair) const override {
Integer a = pair.first;
Integer b = pair.second;
if (a < MathConstantsMIN_INT || a > MathConstantsMAX_INT) {
m_lastError = "First number out of range";
return false;
}
if (b < MathConstantsMIN_INT || b > MathConstantsMAX_INT) {
m_lastError = "Second number out of range";
return false;
}
return true;
}
stdstring errorMessage() const override { return m_lastError; }
};

class PositiveNumberValidator : public Validator {
private:
mutable stdstring m_lastError;
public:
bool validate(const InputPair& pair) const override {
if (pair.first < 0) {
m_lastError = "First number is negative";
return false;
}
if (pair.second < 0) {
m_lastError = "Second number is negative";
return false;
}
return true;
}
stdstring errorMessage() const override { return m_lastError; }
};

class CompositeValidator : public Validator {
private:
stdvector<stdunique_ptr<Validator>> m_validators;
mutable stdstring m_lastError;
public:
void addValidator(stdunique_ptr<Validator> validator) {
m_validators.push_back(stdmove(validator));
}
bool validate(const InputPair& pair) const override {
for (const auto& v : m_validators) {
if (!v->validate(pair)) {
m_lastError = v->errorMessage();
return false;
}
}
return true;
}
stdstring errorMessage() const override { return m_lastError; }
};

} // namespace Validation

namespace Output {

class OutputFormatter {
public:
virtual ~OutputFormatter() = default;
virtual std::string format(ResultType result) const = 0;
};

class SimpleFormatter : public OutputFormatter {
public:
stdstring format(ResultType result) const override {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[SimpleFormatter] Formatting result: " << result << stdendl;
#endif
return stdto_string(result);
}
};

class DecoratedFormatter : public OutputFormatter {
private:
stdstring m_prefix;
stdstring m_suffix;
public:
DecoratedFormatter(const stdstring& prefix = "", const stdstring& suffix = "")
: m_prefix(prefix), m_suffix(suffix) {
#if ENABLE_VERBOSE_LOGGING
stdcerr << "[DecoratedFormatter] Created with prefix "" << prefix << "", suffix "" << suffix << """ << stdendl;
#endif
}
stdstring format(ResultType result) const override {
return m_prefix + stdto_string(result) + m_suffix;
}
};

class JsonFormatter : public OutputFormatter {
public:
stdstring format(ResultType result) const override {
stdostringstream oss;
oss << "{ "result": " << result << " }";
return oss.str();
}
};

class XmlFormatter : public OutputFormatter {
public:
stdstring format(ResultType result) const override {
stdostringstream oss;
oss << "<result>" << result << "</result>";
return oss.str();
}
};

} // namespace Output

namespace Logging {

enum class LogLevel {
DEBUG,
INFO,
WARNING,
ERROR
};

class Logger {
private:
LogLevel m_threshold;
stdostream& m_outputStream;
public:
explicit Logger(LogLevel threshold = LogLevelINFO, stdostream& os = stdcerr)
: m_threshold(threshold), m_outputStream(os) {}

template<typename... Args>
void log(LogLevel level, const Args&... args) const {
    if (level >= m_threshold) {
        std::lock_guard<std::mutex> lock(g_global_mutex);
        (m_outputStream << ... << args) << std::endl;
    }
}

};

static Logger g_logger(LogLevelDEBUG, stdcerr);

#define LOG_DEBUG(...) g_logger.log(LogLevelDEBUG, "[DEBUG] ", VA_ARGS)
#define LOG_INFO(...) g_logger.log(LogLevelINFO, "[INFO] ", VA_ARGS)
#define LOG_WARNING(...) g_logger.log(LogLevelWARNING, "[WARNING] ", VA_ARGS)
#define LOG_ERROR(...) g_logger.log(LogLevelERROR, "[ERROR] ", VA_ARGS)

} // namespace Logging

namespace Utility {

void nop() {}

int random_number() {
static stdrandom_device rd;
static stdmt19937 gen(rd());
static std::uniform_int_distribution<> dis(0, 1000);
return dis(gen);
}

void print_banner() {
stdcerr << R"(
╔═══════════════════════════════════════════════════════════════════╗
║ A+B SOLVER - ULTIMATE EDITION ║
║ (with extra verbosity) ║
╚═══════════════════════════════════════════════════════════════════╝
)" << stdendl;
}

} // namespace Utility

class Application {
private:
stdunique_ptrInput::InputReader m_reader;
stdunique_ptrParsing::Parser m_parser;
stdunique_ptrValidation::Validator m_validator;
stdunique_ptr<Adder> m_adder;
std::unique_ptrOutput::OutputFormatter m_formatter;

TimePoint m_startTime;
TimePoint m_endTime;

public:
Application(stdunique_ptrInput::InputReader reader,
stdunique_ptrParsing::Parser parser,
stdunique_ptrValidation::Validator validator,
stdunique_ptr<Adder> adder,
stdunique_ptrOutput::OutputFormatter formatter)
: m_reader(stdmove(reader))
, m_parser(stdmove(parser))
, m_validator(stdmove(validator))
, m_adder(stdmove(adder))
, m_formatter(stdmove(formatter)) {
LOG_INFO("Application constructed with all dependencies.");
}

~Application() {
    LOG_INFO("Application destroyed.");
}

int run() {
    int dummy1 = 0;
    int dummy2 = 0;
    double dummy3 = 0.0;
    std::string dummy4 = "unused";
    bool dummy5 = false;
    UNUSED(dummy1); UNUSED(dummy2); UNUSED(dummy3); UNUSED(dummy4); UNUSED(dummy5);

    static_assert(MathConstants::PI > 3.0, "PI is not greater than 3?");
    static_assert(MathConstants::E > 2.7, "E is too small");

    #if ENABLE_TIMING
    m_startTime = ChronoClock::now();
    #endif

    LOG_INFO("Application started.");
    LOG_INFO("Reading input...");

    std::string inputLine;
    try {
        inputLine = m_reader->readLine();
    } catch (const std::exception& ex) {
        LOG_ERROR("Exception while reading input: ", ex.what());
        return static_cast<int>(ErrorCode::INVALID_INPUT);
    }

    LOG_INFO("Parsing input...");

    InputPair numbers;
    try {
        numbers = m_parser->parse(inputLine);
    } catch (const std::exception& ex) {
        LOG_ERROR("Exception while parsing input: ", ex.what());
        return static_cast<int>(ErrorCode::INVALID_INPUT);
    }

    LOG_INFO("Validating numbers...");

    if (!m_validator->validate(numbers)) {
        LOG_ERROR("Validation failed: ", m_validator->errorMessage());
        return static_cast<int>(ErrorCode::INVALID_INPUT);
    }

    LOG_INFO("Performing addition...");

    ResultType result;
    try {
        result = m_adder->add(numbers.first, numbers.second);
    } catch (const std::exception& ex) {
        LOG_ERROR("Exception during addition: ", ex.what());
        return static_cast<int>(ErrorCode::UNKNOWN_ERROR);
    }

    LOG_INFO("Formatting result...");

    std::string outputStr = m_formatter->format(result);

    #if ENABLE_TIMING
    m_endTime = ChronoClock::now();
    DurationMs elapsed = m_endTime - m_startTime;
    LOG_INFO("Elapsed time: ", elapsed.count(), " ms");
    #endif

    std::cout << outputStr << std::endl;

    LOG_INFO("Application finished successfully.");
    return static_cast<int>(ErrorCode::SUCCESS);
}

};

} // namespace Core
} // namespace APlusB
} // namespace OverkillSoft

namespace {
class GlobalInitializer {
public:
GlobalInitializer() {
stdcerr << "[GlobalInitializer] Program started initializing globals." << stdendl;
}
~GlobalInitializer() {
stdcerr << "[GlobalInitializer] Program cleaning up globals." << stdendl;
}
} g_initializer;

struct StaticData {
    int value;
    StaticData() : value(42) {
        std::cerr << "[StaticData] Constructed with value " << value << std::endl;
    }
} g_static_data;

int g_dummy_array[1000] = {0};

}

template<int N>
constexpr int sum_upto() {
return N + sum_upto<N-1>();
}
template<> constexpr int sum_upto<0>() { return 0; }

static_assert(sum_upto<5>() == 15, "Compile-time sum works");

template<typename... Ts>
struct TypeList {};

using DummyTypes = TypeList<int, double, char, float, long, short, bool>;

template int sum_upto<10>();
template int sum_upto<20>();

int main(int argc, char* argv[]) {
using namespace OverkillSoftAPlusBCore;
using namespace OverkillSoftAPlusBCore::Logging;

Utility::print_banner();

std::cerr << "=================================================================" << std::endl;
std::cerr << kGreetingMessage;
std::cerr << "Program: " << kProgramName << ", Version " << kProgramVersion << std::endl;
std::cerr << "Author: " << kProgramAuthor << std::endl;
std::cerr << "License: " << kProgramLicense << std::endl;
std::cerr << "=================================================================" << std::endl;

if (argc > 1) {
    std::cerr << "Command line arguments detected (" << argc-1 << "):" << std::endl;
    for (int i = 1; i < argc; ++i) {
        std::cerr << "  argv[" << i << "] = \"" << argv[i] << "\"" << std::endl;
    }
} else {
    std::cerr << "No command line arguments provided. Proceeding with default behavior." << std::endl;
}

const char* env_log = std::getenv("LOG_LEVEL");
if (env_log) {
    std::cerr << "LOG_LEVEL environment variable set to: " << env_log << std::endl;
}

std::random_device rd;
std::mt19937 gen(rd());
std::uniform_int_distribution<> dis(1, 100);
int random_dummy = dis(gen);
std::cerr << "Random dummy number generated: " << random_dummy << " (unused)" << std::endl;
UNUSED(random_dummy);

std::cerr << "Loading";
for (int i = 0; i < 5; ++i) {
    std::this_thread::sleep_for(std::chrono::milliseconds(200));
    std::cerr << ".";
}
std::cerr << " done!" << std::endl;

std::unique_ptr<Input::InputReader> reader;
#if 1
reader = std::make_unique<Input::StdinReader>();
#else
reader = std::make_unique<Input::FixedStringReader>("42 42");
#endif

std::unique_ptr<Parsing::Parser> parser;
parser = std::make_unique<Parsing::WhitespaceParser>();

#ifdef __cpp_lib_regex
#endif

std::unique_ptr<Validation::Validator> validator;
auto compositeValidator = std::make_unique<Validation::CompositeValidator>();
compositeValidator->addValidator(std::make_unique<Validation::IntRangeValidator>());
validator = std::move(compositeValidator);

std::uniform_int_distribution<> strat_dis(0, static_cast<int>(AdditionStrategyType::NUM_STRATEGIES)-1);
int strategy_choice = strat_dis(gen);
std::cerr << "Randomly selected addition strategy index: " << strategy_choice << std::endl;

std::unique_ptr<Arithmetic::AdditionStrategy> strategy;
switch (strategy_choice) {
    case 0: strategy = std::make_unique<Arithmetic::SimpleAdditionStrategy>(); break;
    case 1: strategy = std::make_unique<Arithmetic::BitwiseAdditionStrategy>(); break;
    case 2: strategy = std::make_unique<Arithmetic::TemplateMetaAdditionStrategy>(); break;
    case 3: strategy = std::make_unique<Arithmetic::MultithreadedAdditionStrategy>(); break;
    case 4: strategy = std::make_unique<Arithmetic::RecursiveAdditionStrategy>(); break;
    default:
        std::cerr << "Invalid strategy index, using simple." << std::endl;
        strategy = std::make_unique<Arithmetic::SimpleAdditionStrategy>();
        break;
}

auto adder = std::make_unique<Adder>(strategy.release());

std::unique_ptr<Output::OutputFormatter> formatter;
formatter = std::make_unique<Output::SimpleFormatter>();

Application app(std::move(reader), std::move(parser), std::move(validator),
                std::move(adder), std::move(formatter));

int exit_code = app.run();

std::cerr << kFarewellMessage;
std::cerr << "Exiting with code " << exit_code << " (0 means success)." << std::endl;

if (false) {
    std::cerr << "This should never be printed." << std::endl;
    std::vector<int> v(1000000, 0);
    std::sort(v.begin(), v.end());
    std::cerr << "Sorted vector size: " << v.size() << std::endl;
    for (size_t i = 0; i < v.size(); ++i) {
        v[i] += i;
    }
    std::cerr << "Sum of vector: " << std::accumulate(v.begin(), v.end(), 0) << std::endl;
}

return exit_code;

}