//#(compile) c++; compiler:g132; options:-O3 -std=c++23; libs:-
// https://godbolt.org/z/9s94nbrx3
#include <future>
#include <thread>
#include <iostream>
int ack(int m, int n); // Ackermann function
int main () {
std::packaged_task<int(void)> task1 { // Signature of the remaining function
[]{ return ack(3,11);} }; // prepare ack(3,11)
auto f1 = task1.get_future(); // Communication channel
std::jthread th1 { move(task1) }; // in new thread
std::cout << " ack(3,11):" << f1.get() // Retrieve result
<< '\n'; // Output: ack(3,11):16381
}