#include <iostream>
#include <future>
#include <stdexcept>
#include <thread>

using namespace std ;

// Function that runs in the worker thread and throws an exception
void throw_exception_function()
{
    cout << "Worker thread ID: " << this_thread::get_id() << endl;
    // Simulate some work
    throw runtime_error("Something went wrong in the worker thread!");
}

int main()
{
    try
    {
        // Use async to run the function asynchronously.
        // It returns a future object.
        future<void> future_result = async(launch::async, throw_exception_function);

        cout << "Main thread ID: " << this_thread::get_id() << endl;
        cout << "Waiting for the worker thread to finish..." << endl;

        // Call .get() on the future. If the function threw an exception,
        // .get() will re-throw that exact exception in the main thread.
        future_result.get();

    }
    catch (const runtime_error& e)
    {
        cerr << "Caught exception in main: " << e.what() << endl;
    }
    catch (...)
    {
        cerr << "Caught an unknown exception in main." << endl;
    }

    return 0;
}