Async Future Sum

Launch a small asynchronous task and collect its value through a future.

async_future_sum.cpp

#include <future>
#include <iostream>

int computeSubtotal(int base) {
    int doubled = base * 2;
    return doubled + 1;
}

int main() {
    int base = ;

    auto subtotal = std::async(std::launch::async, computeSubtotal, base);

    int result = subtotal.get();
    int finalScore = result + base;

    std::cout << "base=" << base << std::endl;
    std::cout << "final=" << finalScore << std::endl;
    return 0;
}

#include <future>
#include <iostream>

int computeSubtotal(int base) {
    int doubled = base * 2;
    return doubled + 1;
}

int main() {
    int base = ;

    auto subtotal = std::async(std::launch::async, computeSubtotal, base);

    int result = subtotal.get();
    int finalScore = result + base;

    std::cout << "base=" << base << std::endl;
    std::cout << "final=" << finalScore << std::endl;
    return 0;
}

#include <future>
#include <iostream>

int computeSubtotal(int base) {
    int doubled = base * 2;
    return doubled + 1;
}

int main() {
    int base = ;

    auto subtotal = std::async(std::launch::async, computeSubtotal, base);

    int result = subtotal.get();
    int finalScore = result + base;

    std::cout << "base=" << base << std::endl;
    std::cout << "final=" << finalScore << std::endl;
    return 0;
}

future `std::future::get()` waits for the asynchronous task and returns its result.

task The task body is separate from the caller, so replay can show a worker thread producing the subtotal before the caller uses it.