The Modern C++ Challenge

63. Parallel min and max element algorithms using asynchronous functions

The only difference between this problem and the previous one is how the parallelism is achieved. For the previous problem, the use of threads was required. For this one, you must use asynchronous functions. A function can be executed asynchronously with std::async(). This function creates a promise, which is an asynchronous provider of the result of a function executed asynchronously. A promise has a shared state (which can store either the return value of a function or an exception that resulted from the execution of the function) and an associated future object that provides access to the shared state from a different thread. The promise-future pair defines a channel ...