#include <future> #include <thread> #include <vector> #include <iostream> #include <mutex> // 標準出力のmutex std::mutex mtx_; int long_calc(int i) { std::this_thread::sleep_for(std::chrono::milliseconds(1000)); mtx_.lock(); std::cout << "a" << i << std::endl; mtx_.unlock(); std:</mutex></iostream></vector></thread></future>…