#include <iostream>
#include "rxcpp/rx.hpp"

int main() {
  rxcpp::subjects::subject<int> subject;
  auto subscriber = subject.get_subscriber();
  auto observable = subject.get_observable();

  auto first_num = observable | rxcpp::operators::filter([] (int i) {
    return i == 10;
  }) | rxcpp::operators::first();

  first_num.subscribe([] (int i) {
    std::cout << i << std::endl;
  });

  subscriber.on_next(1);
  subscriber.on_next(2);
  subscriber.on_next(10);
  subscriber.on_completed();

  return 0;
}