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#include <iostream>

using namespace std;

int test_fun()
{
  int a;
  return a;
}


int main(int argc, char* argv[]) {
  int num = argc - 1;

  int * a = nullptr; // intentional mistake
  *a = 9;

  if (num = 0) {
    cout << "No arguments provided\n";
  } else if (num == 0) {  // intentional mistake
    cout << "1 argument provided\n";
  } else if (num == 2) {
    cout << "2 arguments provided\n";
  } else {
    cout << num << " arguments provided\n";
  }
  if (argv != 0) {
    cout << "argv not null\n";;  // intentional extra-semicolon
  }
  if (argv == nullptr) {
    return **argv;  // intentional nullptr dereference
  }

  return 0;
}

#include <chrono>
#include <cinttypes>
#include <cstdio>
#include <memory>
#include <string>
#include <utility>

#include "rclcpp/rclcpp.hpp"
#include "std_msgs/msg/int32.hpp"

using namespace std::chrono_literals;

// Node that produces messages.
struct Producer : public rclcpp::Node
{
  Producer(const std::string & name, const std::string & output)
  : Node(name, rclcpp::NodeOptions().use_intra_process_comms(true))
  {
    // Create a publisher on the output topic.
    pub_ = this->create_publisher<std_msgs::msg::Int32>(output, 10);
    std::weak_ptr<std::remove_pointer<decltype(pub_.get())>::type> captured_pub = pub_;
    // Create a timer which publishes on the output topic at ~1Hz.
    auto callback = [captured_pub]() -> void {
        auto pub_ptr = captured_pub.lock();
        if (!pub_ptr) {
          return;
        }
        static int32_t count = 0;
        std_msgs::msg::Int32::UniquePtr msg(new std_msgs::msg::Int32());
        msg->data = count++;
        printf(
          "Published message with value: %d, and address: 0x%" PRIXPTR "\n", msg->data,
          reinterpret_cast<std::uintptr_t>(msg.get()));
        pub_ptr->publish(std::move(msg));
      };
    timer_ = this->create_wall_timer(1s, callback);
  }

  rclcpp::Publisher<std_msgs::msg::Int32>::SharedPtr pub_;
  rclcpp::TimerBase::SharedPtr timer_;
};

// Node that consumes messages.
struct Consumer : public rclcpp::Node
{
  Consumer(const std::string & name, const std::string & input)
  : Node(name, rclcpp::NodeOptions().use_intra_process_comms(true))
  {
    // Create a subscription on the input topic which prints on receipt of new messages.
    sub_ = this->create_subscription<std_msgs::msg::Int32>(
      input,
      10,
      [](std_msgs::msg::Int32::UniquePtr msg) {
        printf(
          " Received message with value: %d, and address: 0x%" PRIXPTR "\n", msg->data,
          reinterpret_cast<std::uintptr_t>(msg.get()));
      });
  }

  rclcpp::Subscription<std_msgs::msg::Int32>::SharedPtr sub_;
};

int main(int argc, char * argv[])
{
  setvbuf(stdout, NULL, _IONBF, BUFSIZ);
  rclcpp::init(argc, argv);
  rclcpp::executors::SingleThreadedExecutor executor;

  auto producer = std::make_shared<Producer>("producer", "number");
  auto consumer = std::make_shared<Consumer>("consumer", "number");

  executor.add_node(producer);
  executor.add_node(consumer);
  executor.spin();

  rclcpp::shutdown();

  return 0;
}

/// Create and return a callback group.
RCLCPP_PUBLIC
rclcpp::CallbackGroup::SharedPtr
create_callback_group(
  rclcpp::CallbackGroupType group_type,
  bool automatically_add_to_executor_with_node = true);