parallel_for.cpp

/*
 * Copyright 2021 Jeisson Hidalgo-Cespedes - Universidad de Costa Rica
 * Creates a secondary thread that greets in the standard output
 */

#include <omp.h>

#include <cstdlib>
#include <iostream>

int main(int argc, char* argv[]) {
  int thread_count = omp_get_max_threads();
  if (argc >= 2) {
    thread_count = atoi(argv[1]);
  }

  int iteration_count = thread_count;
  if (argc >= 3) {
    iteration_count = atoi(argv[2]);
  }

  // ...
  #pragma omp parallel for num_threads(thread_count) \
     default(none) shared(std::cout, iteration_count)
  for (int iteration = 0; iteration < iteration_count; ++iteration) {
    // ...
    #pragma omp critical(cout)
    std::cout << omp_get_thread_num() << '/' << omp_get_num_threads()
      << ": iteration " << iteration << '/' << iteration_count << std::endl;
    // ...
  }
  // ...
  return 0;
}